refactor(#3309): extract health-diagnostic-types leaf module, wire RULES

Wiring all 8 rule-group files into health-diagnostic.cts's RULES array
created a genuine CJS circular dependency: each group file required
health-diagnostic.cjs back for the shared enums, and health-diagnostic.cjs
now required the group files forward, so the enums were undefined
mid-load (destructuring health-diagnostic.cjs's still-unassigned
exports).

Fixes it by splitting the enums/types (SEVERITY, REMEDY_ACTION,
REMEDY_RISK, Remedy, Diagnostic, Rule) into a dependency-free leaf
module, health-diagnostic-types.cts, that both sides import instead of
each other. health-diagnostic.cts re-exports the enums for existing
consumers. RULES is now the real concatenation of all 8 groups (31
codes — E001 intentionally stays a pre-check outside the table).

src/health-diagnostic-rules/agent-install.cts

@@ -24,8 +24,8 @@
  *         ("Rule table organization" — Agent installation group)
  */
 
-// eslint-disable-next-line @typescript-eslint/no-require-imports -- health-diagnostic.cjs is an export= CommonJS module
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports -- health-diagnostic-types.cjs is an export= CommonJS module
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Rule = healthDiagnosticMod.Rule;
 type Diagnostic = healthDiagnosticMod.Diagnostic;

src/health-diagnostic-rules/config-validation.cts

@@ -54,8 +54,8 @@ import type planningSnapshotMod = require('../planning-snapshot.cjs');
 
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
-// eslint-disable-next-line @typescript-eslint/no-require-imports -- health-diagnostic.cjs is an export= CommonJS module
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports -- health-diagnostic-types.cjs is an export= CommonJS module
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Diagnostic = healthDiagnosticMod.Diagnostic;
 type Remedy = healthDiagnosticMod.Remedy;

src/health-diagnostic-rules/milestone-archive-hygiene.cts

@@ -22,7 +22,7 @@ import type planningSnapshotMod = require('../planning-snapshot.cjs');
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
 // eslint-disable-next-line @typescript-eslint/no-require-imports
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Diagnostic = healthDiagnosticMod.Diagnostic;
 type Rule = healthDiagnosticMod.Rule;

src/health-diagnostic-rules/phase-structure.cts

@@ -44,7 +44,7 @@ import type planningSnapshotMod = require('../planning-snapshot.cjs');
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
 // eslint-disable-next-line @typescript-eslint/no-require-imports
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Diagnostic = healthDiagnosticMod.Diagnostic;
 type Rule = healthDiagnosticMod.Rule;

src/health-diagnostic-rules/roadmap-disk-consistency.cts

@@ -87,7 +87,7 @@ import type planningSnapshotMod = require('../planning-snapshot.cjs');
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
 // eslint-disable-next-line @typescript-eslint/no-require-imports
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Diagnostic = healthDiagnosticMod.Diagnostic;
 type Rule = healthDiagnosticMod.Rule;

src/health-diagnostic-rules/root-existence.cts

@@ -22,7 +22,7 @@ import type planningSnapshotMod = require('../planning-snapshot.cjs');
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
 // eslint-disable-next-line @typescript-eslint/no-require-imports
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Diagnostic = healthDiagnosticMod.Diagnostic;
 type Rule = healthDiagnosticMod.Rule;

src/health-diagnostic-rules/state-consistency.cts

@@ -42,7 +42,7 @@
 // — unlike `health-diagnostic.cts`'s own type-only import of
 // `planning-snapshot.cjs`, which never touches that module's runtime values.
 // eslint-disable-next-line @typescript-eslint/no-require-imports -- export= CommonJS module
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Rule = healthDiagnosticMod.Rule;
 type Diagnostic = healthDiagnosticMod.Diagnostic;

src/health-diagnostic-rules/worktree-health.cts

@@ -64,7 +64,7 @@ import type planningSnapshotMod = require('../planning-snapshot.cjs');
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
 // eslint-disable-next-line @typescript-eslint/no-require-imports
-import healthDiagnosticMod = require('../health-diagnostic.cjs');
+import healthDiagnosticMod = require('../health-diagnostic-types.cjs');
 const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticMod;
 type Diagnostic = healthDiagnosticMod.Diagnostic;
 type Rule = healthDiagnosticMod.Rule;

src/health-diagnostic-types.cts

@@ -0,0 +1,104 @@
+/**
+ * Health Diagnostic Types — shared, dependency-free rule-table types (Phase
+ * 11, #3309, ADR-3180 §8.2/§8.3/§8.5).
+ *
+ * Split out from `src/health-diagnostic.cts` to break a CJS circular
+ * dependency between the evaluator and its own rule-group files
+ * (`src/health-diagnostic-rules/*.cts`): those files need the frozen
+ * `SEVERITY`/`REMEDY_ACTION`/`REMEDY_RISK` enums and the `Diagnostic`/
+ * `Remedy`/`Rule` shapes, but the evaluator (`health-diagnostic.cts`) also
+ * needs to `require()` every rule-group file to populate its `RULES` array —
+ * a rule-group file requiring `health-diagnostic.cjs` back, mid-load, reads
+ * `module.exports` before it is assigned, so the destructured enums come
+ * back `undefined`. This leaf has NO runtime dependency on anything in that
+ * cycle, so both sides can depend on it directly.
+ *
+ * Design: .gsd/phase/refactor-3309-health-diagnostic-rule-table/40-design.md
+ * Test matrix: .gsd/phase/refactor-3309-health-diagnostic-rule-table/50-test-matrix.md
+ *
+ * ADR-457 build-at-publish: source in src/health-diagnostic-types.cts,
+ * compiled to gsd-core/bin/lib/health-diagnostic-types.cjs (gitignored).
+ */
+
+// eslint-disable-next-line @typescript-eslint/no-require-imports -- type-only; erased at compile time, no runtime require emitted
+import type planningSnapshotMod = require('./planning-snapshot.cjs');
+
+type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
+
+// ─── Severity ───────────────────────────────────────────────────────────────
+
+const SEVERITY = Object.freeze({
+  ERROR: 'error',
+  WARNING: 'warning',
+  INFO: 'info',
+});
+type Severity = (typeof SEVERITY)[keyof typeof SEVERITY];
+
+// ─── Remedy action / risk ───────────────────────────────────────────────────
+
+// Harvested from health.md's published table + the corrected 6-action
+// implementation (`src/verify.cts:2405-2553`) — not 5; `addAiIntegrationPhaseKey`
+// (verify.cts:1860/2481-2502) was live in code, missing from docs (design
+// doc, "Ground truth vs. issue #3309's claims" section).
+const REMEDY_ACTION = Object.freeze({
+  CREATE_CONFIG: 'createConfig',
+  RESET_CONFIG: 'resetConfig',
+  REGENERATE_STATE: 'regenerateState',
+  ADD_NYQUIST_KEY: 'addNyquistKey',
+  ADD_AI_INTEGRATION_PHASE_KEY: 'addAiIntegrationPhaseKey',
+  BACKFILL_MILESTONES: 'backfillMilestones',
+  // §8.3 rule 5 — every non-repairable finding's `fix` string becomes an
+  // ADVISE payload; ADVISE never acts, only describes.
+  ADVISE: 'advise',
+});
+type RemedyAction = (typeof REMEDY_ACTION)[keyof typeof REMEDY_ACTION];
+
+const REMEDY_RISK = Object.freeze({
+  NONE: 'none',
+  DESTRUCTIVE: 'destructive',
+});
+type RemedyRisk = (typeof REMEDY_RISK)[keyof typeof REMEDY_RISK];
+
+// ─── Diagnostic / Rule shapes ───────────────────────────────────────────────
+
+interface Remedy {
+  action: RemedyAction;
+  risk: RemedyRisk;
+  args: Record<string, unknown>;
+}
+
+interface Diagnostic {
+  code: string; // e.g. 'W010' — append-only, never renumbered (§8.2 rule 2)
+  severity: Severity; // property of the RULE, never the emit call (§8.2 rule 3)
+  message: string;
+  remedy: Remedy;
+}
+
+interface Rule {
+  code: string;
+  severity: Severity;
+  check: (snapshot: PlanningSnapshot) => Diagnostic[]; // §8.1 rule 1 signature, verbatim
+}
+
+// ─── Exports ────────────────────────────────────────────────────────────────
+
+const healthDiagnosticTypes = {
+  SEVERITY,
+  REMEDY_ACTION,
+  REMEDY_RISK,
+};
+
+// Namespace merge (same binding name as the value above) is how a CommonJS
+// `export =` module exposes a type alongside its runtime export — `export
+// type` is rejected by TS2309 ("An export assignment cannot be used in a
+// module with other exported elements") when combined with `export =`, so
+// these types ride along on the exported object via declaration merging
+// instead. Mirrors `src/planning-scope.cts`'s exact mechanism. Consumers
+// doing `import x = require('./health-diagnostic-types.cjs')` can reference
+// the types as `x.Severity`, `x.RemedyAction`, etc.
+// eslint-disable-next-line @typescript-eslint/no-namespace
+declare namespace healthDiagnosticTypes {
+  export { Severity, RemedyAction, RemedyRisk, Remedy, Diagnostic, Rule };
+}
+
+export = healthDiagnosticTypes;

src/health-diagnostic.cts

@@ -30,68 +30,55 @@ import type planningSnapshotMod = require('./planning-snapshot.cjs');
 
 type PlanningSnapshot = ReturnType<typeof planningSnapshotMod.buildPlanningSnapshot>;
 
-// ─── Severity ───────────────────────────────────────────────────────────────
-
-const SEVERITY = Object.freeze({
-  ERROR: 'error',
-  WARNING: 'warning',
-  INFO: 'info',
-});
-type Severity = (typeof SEVERITY)[keyof typeof SEVERITY];
-
-// ─── Remedy action / risk ───────────────────────────────────────────────────
-
-// Harvested from health.md's published table + the corrected 6-action
-// implementation (`src/verify.cts:2405-2553`) — not 5; `addAiIntegrationPhaseKey`
-// (verify.cts:1860/2481-2502) was live in code, missing from docs (design
-// doc, "Ground truth vs. issue #3309's claims" section).
-const REMEDY_ACTION = Object.freeze({
-  CREATE_CONFIG: 'createConfig',
-  RESET_CONFIG: 'resetConfig',
-  REGENERATE_STATE: 'regenerateState',
-  ADD_NYQUIST_KEY: 'addNyquistKey',
-  ADD_AI_INTEGRATION_PHASE_KEY: 'addAiIntegrationPhaseKey',
-  BACKFILL_MILESTONES: 'backfillMilestones',
-  // §8.3 rule 5 — every non-repairable finding's `fix` string becomes an
-  // ADVISE payload; ADVISE never acts, only describes.
-  ADVISE: 'advise',
-});
-type RemedyAction = (typeof REMEDY_ACTION)[keyof typeof REMEDY_ACTION];
-
-const REMEDY_RISK = Object.freeze({
-  NONE: 'none',
-  DESTRUCTIVE: 'destructive',
-});
-type RemedyRisk = (typeof REMEDY_RISK)[keyof typeof REMEDY_RISK];
-
-// ─── Diagnostic / Rule shapes ───────────────────────────────────────────────
-
-interface Remedy {
-  action: RemedyAction;
-  risk: RemedyRisk;
-  args: Record<string, unknown>;
-}
-
-interface Diagnostic {
-  code: string; // e.g. 'W010' — append-only, never renumbered (§8.2 rule 2)
-  severity: Severity; // property of the RULE, never the emit call (§8.2 rule 3)
-  message: string;
-  remedy: Remedy;
-}
-
-interface Rule {
-  code: string;
-  severity: Severity;
-  check: (snapshot: PlanningSnapshot) => Diagnostic[]; // §8.1 rule 1 signature, verbatim
-}
+// Runtime values (SEVERITY/REMEDY_ACTION/REMEDY_RISK) are needed here — not
+// just types — for `applyRepairs`'s comparisons, so this is a normal
+// (non type-only) `import ... = require(...)`. `health-diagnostic-types.cjs`
+// is the leaf module these enums/types were extracted to, so that this file
+// can `require()` every rule-group file below without a circular dependency
+// (see that module's file-level comment for the full explanation).
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import healthDiagnosticTypesMod = require('./health-diagnostic-types.cjs');
+const { SEVERITY, REMEDY_ACTION, REMEDY_RISK } = healthDiagnosticTypesMod;
+type Severity = healthDiagnosticTypesMod.Severity;
+type RemedyAction = healthDiagnosticTypesMod.RemedyAction;
+type RemedyRisk = healthDiagnosticTypesMod.RemedyRisk;
+type Remedy = healthDiagnosticTypesMod.Remedy;
+type Diagnostic = healthDiagnosticTypesMod.Diagnostic;
+type Rule = healthDiagnosticTypesMod.Rule;
 
 // ─── Rule table ─────────────────────────────────────────────────────────────
 
-// Starts EMPTY. A later migration batch appends each of the 32 rule
-// functions extracted from `cmdValidateHealth` (design doc, "Rule table
-// organization" section) — this phase establishes only the container and its
-// type.
-const RULES: Rule[] = [];
+// Populated by concatenating each rule group's exported `RULES` array (design
+// doc, "Rule table organization" section) — the 32 rule functions extracted
+// from `cmdValidateHealth`, `src/verify.cts:1616-2577`.
+
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import rootExistenceMod = require('./health-diagnostic-rules/root-existence.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import stateConsistencyMod = require('./health-diagnostic-rules/state-consistency.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import configValidationMod = require('./health-diagnostic-rules/config-validation.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import phaseStructureMod = require('./health-diagnostic-rules/phase-structure.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import agentInstallMod = require('./health-diagnostic-rules/agent-install.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import roadmapDiskConsistencyMod = require('./health-diagnostic-rules/roadmap-disk-consistency.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import worktreeHealthMod = require('./health-diagnostic-rules/worktree-health.cjs');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import milestoneArchiveHygieneMod = require('./health-diagnostic-rules/milestone-archive-hygiene.cjs');
+
+const RULES: Rule[] = [
+  ...rootExistenceMod.RULES,
+  ...stateConsistencyMod.RULES,
+  ...configValidationMod.RULES,
+  ...phaseStructureMod.RULES,
+  ...agentInstallMod.RULES,
+  ...roadmapDiskConsistencyMod.RULES,
+  ...worktreeHealthMod.RULES,
+  ...milestoneArchiveHygieneMod.RULES,
+];
 
 // ─── Evaluator ──────────────────────────────────────────────────────────────