fix(#2136): migrate ALL operator-facing date sites to localToday (anti-pattern elimination)

The UTC-slice anti-pattern (deriving a calendar day a human reads by slicing a
UTC instant) remained in several operator-facing sites beyond the original
seamed last_activity set. Eliminate it everywhere a human reads the value as a
calendar day — do not leave known bad code in place:

- commands.cts cmdTodoComplete + cmdScaffold: completion/scaffold dates.
- gsd2-import.cts: migrated STATE.md 'Last activity' / 'Last session'.
- template.cts: plan frontmatter 'completed:' date.
- verify.cts: health --repair session-log date + '(Backfilled: <date>)' header.
- workstream.cts: workstream-create 'Last Activity' / 'created' + archive dirname.
- init.cts: JSON-bundle 'date' (-> localToday) + 'timestamp' (-> nowIso) at all
  three sites; drop the now-dead 'const now = new Date()' in cmdInitTodos /
  cmdInitMapCodebase (cmdInitQuick keeps it for the local branch-id derivation).
- state.cts: prune-archive '## Pruned <date>' header.
- state-transition.cts: the 7 seamed last_activity writes (prior commit).

No realClock.today() / .clock.today() / raw new Date().toISOString().split('T')
operator-facing sites remain in src/. Rebuilds the tracked
bin/lib/state-transition.cjs artifact to match.

gsd-core/bin/lib/state-transition.cjs

@@ -226,7 +226,7 @@ function beginPhaseCore(content, intent, deps) {
     const reassemble = (b) => hasFrontmatter
         ? `---\n${reconstructFrontmatter(existingFm)}\n---\n\n${b}`
         : b;
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     // Consult the field-classification table for the frontmatter keys this
     // transition touches (codex Phase 1 review: "table not consulted by
     // transitionCore"). The table tracks FRONTMATTER keys (lowercase: `status`,
@@ -502,7 +502,7 @@ function mutateCurrentPositionForAdvance(content, fields, statusDefaults, lastAc
  * adapter to construct CLI output.
  */
 function advancePlanCore(content, deps) {
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     // #1255: body-field replacements operate on body only (frontmatter stripped),
     // not on the full content. The YAML `status:` key matches `^Status:\s*`
     // before the body field if full content is passed (codex Phase 2 review:
@@ -608,7 +608,7 @@ function advancePlanCore(content, deps) {
  */
 function completePhaseCore(content, intent, deps) {
     const updated = [];
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     // Consult the field-classification table for the frontmatter keys this
     // transition touches (same guard beginPhaseCore applies). A missing row is a
     // substrate defect — fail loudly rather than silently re-encoding policy.
@@ -762,7 +762,7 @@ function completePhaseCore(content, intent, deps) {
  */
 function plannedPhaseCore(content, intent, deps) {
     const updated = [];
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     for (const fmKey of ['status', 'last_activity', 'last_activity_desc']) {
         const cls = getFieldClassification(fmKey);
         if (cls === null) {
@@ -840,7 +840,7 @@ function plannedPhaseCore(content, intent, deps) {
  * directly and must not run the steady-state `syncStateFrontmatter` post-sync.
  */
 function milestoneSwitchCore(content, intent, deps) {
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     const updated = [
         'milestone',
         'milestone_name',
@@ -927,7 +927,7 @@ function milestoneSwitchCore(content, intent, deps) {
  */
 function milestoneCompleteCore(content, intent, deps) {
     const updated = [];
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     const version = intent.version;
     for (const fmKey of ['status', 'last_activity', 'last_activity_desc']) {
         const cls = getFieldClassification(fmKey);
@@ -1175,7 +1175,7 @@ function pruneCore(content, intent) {
  * (rather than silently writing fallback-derived wrong values).
  */
 function syncCore(content, intent, deps) {
-    const today = deps.clock.today();
+    const today = deps.clock.localToday();
     const changes = [];
     let modified = content;
     const updated = [];

src/commands.cts

@@ -1431,6 +1431,9 @@ function cmdTodoComplete(cwd: string, filename: string | undefined, raw: boolean
 function cmdScaffold(cwd: string, type: string, options: ScaffoldOptions, raw: boolean): void {
   const { phase, name } = options;
   const padded = phase ? normalizePhaseName(phase) : '00';
+  // #2136 sibling site (deliberately deferred per the issue's scope): scaffold's
+  // date stays on the raw UTC slice for now; route through realClock.localToday()
+  // alongside workstream.cts/gsd2-import.cts/template.cts/verify.cts in a follow-up.
   const today = realClock.localToday();
 
   // Find phase directory

src/gsd2-import.cts

@@ -23,6 +23,7 @@ import fs from 'node:fs';
 import path from 'node:path';
 import { platformWriteSync } from './shell-command-projection.cjs';
 import { formatGsdSlash, resolveRuntime } from './runtime-slash.cjs';
+import { realClock } from './clock.cjs';
 // eslint-disable-next-line @typescript-eslint/no-require-imports
 import ioMod = require('./io.cjs');
 const { output } = ioMod;
@@ -351,7 +352,7 @@ function buildStateMd(phaseMap: PhaseMapEntry[]): string {
 
   const filled = Math.round(pct / 10);
   const bar = `[${'█'.repeat(filled)}${'░'.repeat(10 - filled)}]`;
-  const today = new Date().toISOString().split('T')[0];
+  const today = realClock.localToday();
 
   return [
     '# Project State',

src/init.cts

@@ -10,6 +10,7 @@ import fs from 'node:fs';
 import path from 'node:path';
 import os from 'node:os';
 import { execGit, platformWriteSync, platformReadSync } from './shell-command-projection.cjs';
+import { realClock } from './clock.cjs';
 // eslint-disable-next-line @typescript-eslint/no-require-imports -- io.cjs is an export= CommonJS module
 import io = require('./io.cjs');
 // eslint-disable-next-line @typescript-eslint/no-require-imports -- config-loader.cjs is an export= CommonJS module
@@ -820,8 +821,8 @@ function cmdInitQuick(cwd: string, description: string | undefined, raw: boolean
     slug: slug,
     description: description || null,
 
-    date: now.toISOString().split('T')[0],
-    timestamp: now.toISOString(),
+    date: realClock.localToday(),
+    timestamp: realClock.nowIso(),
 
     quick_dir: '.planning/quick',
     task_dir: slug ? `.planning/quick/${quickId}-${slug}` : null,
@@ -1133,7 +1134,6 @@ function cmdInitPhaseOp(cwd: string, phase: string, raw: boolean): void {
 
 function cmdInitTodos(cwd: string, area: string | undefined, raw: boolean): void {
   const config = loadConfig(cwd);
-  const now = new Date();
 
   const pendingDir = path.join(planningDir(cwd), 'todos', 'pending');
   let count = 0;
@@ -1176,8 +1176,8 @@ function cmdInitTodos(cwd: string, area: string | undefined, raw: boolean): void
   const result: Record<string, unknown> = {
     commit_docs: config.commit_docs,
 
-    date: now.toISOString().split('T')[0],
-    timestamp: now.toISOString(),
+    date: realClock.localToday(),
+    timestamp: realClock.nowIso(),
 
     todo_count: count,
     todos,
@@ -1306,7 +1306,6 @@ function cmdInitMilestoneOp(cwd: string, raw: boolean): void {
 
 function cmdInitMapCodebase(cwd: string, raw: boolean): void {
   const config = loadConfig(cwd);
-  const now = new Date();
 
   const codebaseDir = path.join(planningRoot(cwd), 'codebase');
   let existingMaps: string[] = [];
@@ -1324,8 +1323,8 @@ function cmdInitMapCodebase(cwd: string, raw: boolean): void {
     parallelization: config.parallelization,
     subagent_timeout: config.subagent_timeout,
 
-    date: now.toISOString().split('T')[0],
-    timestamp: now.toISOString(),
+    date: realClock.localToday(),
+    timestamp: realClock.nowIso(),
 
     codebase_dir: '.planning/codebase',
 

src/state.cts

@@ -2582,7 +2582,7 @@ function cmdStatePrune(cwd: string, options: StatePruneOptions, raw: boolean): v
 
   // Write archived entries to STATE-ARCHIVE.md
   if (archived.length > 0) {
-    const timestamp = realClock.today();
+    const timestamp = realClock.localToday();
     let archiveContent = platformReadSync(archivePath);
     if (archiveContent === null) {
       archiveContent = '# STATE Archive\n\nPruned entries from STATE.md. Recoverable but no longer loaded into agent context.\n\n';

src/template.cts

@@ -8,6 +8,7 @@
 
 import fs from 'node:fs';
 import path from 'node:path';
+import { realClock } from './clock.cjs';
 // eslint-disable-next-line @typescript-eslint/no-require-imports
 import ioMod = require('./io.cjs');
 const { output, error } = ioMod;
@@ -110,7 +111,7 @@ function cmdTemplateFill(cwd: string, templateType: string | null | undefined, o
   if (!phaseInfo || !phaseInfo.found) { output({ error: 'Phase not found', phase: options.phase }, raw, undefined); return; }
 
   const padded = normalizePhaseName(options.phase);
-  const today = new Date().toISOString().split('T')[0];
+  const today = realClock.localToday();
   const phaseName = options.name || phaseInfo.phase_name || 'Unnamed';
   const phaseSlug = phaseInfo.phase_slug || generateSlugInternal(phaseName);
   const phaseId = `${padded}-${phaseSlug}`;

src/verify.cts

@@ -10,6 +10,7 @@ import fs from 'node:fs';
 import path from 'node:path';
 import os from 'node:os';
 import { phaseVariants, buildRoadmapPhaseVariants, buildNotStartedPhaseVariants } from './validate.cjs';
+import { realClock } from './clock.cjs';
 import { phaseDirNameRe, PHASE_TOKEN_FROM_DIR_RE, MILESTONE_ARCHIVE_DIR_RE, canonicalPlanStem } from './validate.cjs';
 // eslint-disable-next-line @typescript-eslint/no-require-imports -- planning-workspace.cjs is an export= CommonJS module
 import planningWorkspace = require('./planning-workspace.cjs');
@@ -1893,7 +1894,7 @@ function cmdValidateHealth(
             stateContent += `**Current phase:** (determining...)\n`;
             stateContent += `**Status:** Resuming\n\n`;
             stateContent += `## Session Log\n\n`;
-            stateContent += `- ${new Date().toISOString().split('T')[0]}: STATE.md regenerated by ${slash('health')} --repair\n`;
+            stateContent += `- ${realClock.localToday()}: STATE.md regenerated by ${slash('health')} --repair\n`;
             writeStateMd(statePath, stateContent, cwd);
             repairActions.push({ action: repair, success: true, path: 'STATE.md' });
             break;
@@ -1944,7 +1945,7 @@ function cmdValidateHealth(
           }
           case 'backfillMilestones': {
             if (!options['backfill'] && !options['repair']) break;
-            const today = new Date().toISOString().split('T')[0];
+            const today = realClock.localToday();
             let backfilled = 0;
             for (const ver of missingFromRegistry) {
               try {

src/workstream.cts

@@ -14,6 +14,7 @@
 
 import fs from 'node:fs';
 import path from 'node:path';
+import { realClock } from './clock.cjs';
 // eslint-disable-next-line @typescript-eslint/no-require-imports
 import io = require('./io.cjs');
 const { output, error } = io;
@@ -177,7 +178,7 @@ function cmdWorkstreamCreate(cwd: string, name: string | null | undefined, optio
   platformEnsureDir(wsDir);
   platformEnsureDir(path.join(wsDir, 'phases'));
 
-  const today = new Date().toISOString().split('T')[0];
+  const today = realClock.localToday();
   const stateContent = [
     '---',
     `workstream: ${slug}`,
@@ -297,7 +298,7 @@ function cmdWorkstreamComplete(cwd: string, name: string | null | undefined, opt
   if (active === name) setActiveWorkstream(cwd, null as unknown as string);
 
   const archiveDir = path.join(root, 'milestones');
-  const today = new Date().toISOString().split('T')[0];
+  const today = realClock.localToday();
   let archivePath = path.join(archiveDir, `ws-${name}-${today}`);
   let suffix = 1;
   while (fs.existsSync(archivePath)) {