feat(#918): loop.render-hooks resolver — consume the Capability Registry (ADR-857 phase 3c) (#920)

Add the loop.render-hooks resolver: the first registry-consuming query.
`gsd-tools loop render-hooks <point>` validates the point against the
authoritative canonical 12, reads the registry's materialized byLoopPoint
hooks, filters them by activation, and emits a JSON envelope {point,
activeHooks, rendered} with ordered markdown.

Activation resolves each hook's `when` key by precedence: loadConfig value
(post-cutover federated) -> raw config.json workstream/root single-key lookup
(pre-cutover central override) -> registry configSchema default (so a
default:true capability hook is active out-of-the-box) -> inactive. Guarded
single-value reads only (no merged object built from untrusted keys).

Registry-only: no workflow calls the resolver yet (wiring is the phase-6
cutover). Completes the phase-3 trio.

Closes #918

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

docs/ARCHITECTURE.md

@@ -372,6 +372,7 @@ Node.js CLI utility (`gsd-tools.cjs`) with domain modules split across `gsd-core
 | `profile-output.cjs`       | Profile rendering, USER-PROFILE.md and dev-preferences.md generation                                |
 | `loop-host-contract.cjs`   | Generated Loop Host Contract — 12 loop points, per-step agent roles, and core artifacts; emitted by `scripts/gen-loop-host-contract.cjs` from workflow markers (ADR-894 §3); consumed by `gen-capability-registry.cjs` |
 | `capability-registry.cjs`  | Generated central Capability Registry — role-partitioned index of all co-located capability declarations; emitted by `scripts/gen-capability-registry.cjs` (ADR-894 §5) |
+| `loop-resolver.cjs`        | Loop Extension Point resolver — ADR-857 phase 3c registry-consuming query; filters `byLoopPoint` by config activation, renders active hooks as markdown, emits `{ point, activeHooks, rendered }` envelope; `gsd-tools loop render-hooks <point>` |
 
 
 ---

docs/INVENTORY-MANIFEST.json

@@ -309,6 +309,7 @@
       "learnings.cjs",
       "legacy-cleanup.cjs",
       "loop-host-contract.cjs",
+      "loop-resolver.cjs",
       "milestone.cjs",
       "model-catalog.cjs",
       "model-profiles.cjs",

docs/INVENTORY.md

@@ -370,7 +370,7 @@ The `gsd-planner` agent is decomposed into a core agent plus reference modules t
 
 ---
 
-## CLI Modules (100 shipped)
+## CLI Modules (101 shipped)
 
 Full listing: `gsd-core/bin/lib/*.cjs`.
 
@@ -420,6 +420,7 @@ Full listing: `gsd-core/bin/lib/*.cjs`.
 | `learnings.cjs` | Cross-phase learnings extraction for `/gsd-extract-learnings` |
 | `legacy-cleanup.cjs` | Detect and remove leftover get-shit-done-cc artifacts; exports `planLegacyCleanup` (pure scan) and `applyLegacyCleanup` (thin IO applier) that root out stale files from the old package across every GSD-managed runtime config directory (#607) |
 | `loop-host-contract.cjs` | Generated Loop Host Contract — 12 loop points, per-step agent roles, and core artifacts for the five-step pipeline (discuss/plan/execute/verify/ship); emitted by `scripts/gen-loop-host-contract.cjs --write` (ADR-894 §3); consumed by `gen-capability-registry.cjs` |
+| `loop-resolver.cjs` | Loop Extension Point resolver — ADR-857 phase 3c registry-consuming query; given a canonical loop point, filters `byLoopPoint` by config activation (`when` key traversal with prototype-pollution guard), returns `{ point, activeHooks, rendered }` envelope; `resolveLoopHooks` and `renderLoopHooks` are pure (no I/O); command surface: `gsd-tools loop render-hooks <point>` |
 | `milestone.cjs` | Milestone archival, requirements marking |
 | `model-catalog.cjs` | CJS adapter over the shared model catalog JSON; exports canonical runtime tier defaults, agent profile maps, alias maps, and routing metadata for all CLI consumers |
 | `model-profiles.cjs` | Backward-compatible profile helpers derived from `model-catalog.cjs`; no longer owns its own model table |