feat: add the TechLog Studio asset library route and screen

Adds TECH_LOG_STUDIO_ASSETS (/studio/assets) as a route reachable but
excluded from primary Studio navigation (navigationLabel/navigationOrder
null), plus the AssetLibrary screen that lists assets, shows usage, and
lets an operator archive or hard-delete one. canHardDelete() is a pure
gate mirroring the server's ASSET_IN_USE rule so the screen never offers
an action the server would refuse.

Adding a 28th route also required updating the route-scoped CI
accessibility-evidence gate (FE-GATE-009 in config/ci/gates.json, plus
its authority-baseline counts and shape digest in
scripts/contracts/ci-gates.ts) and the Vite route-to-chunk map that
scripts/generate-build-manifest.ts depends on, or test:unit and the
production build both fail. See task-11-report.md for the full
breakdown.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

scripts/contracts/ci-gates.ts

@@ -446,7 +446,9 @@ export type LoadCiGateContractOptions = Readonly<{
 const CANONICAL_GATE_SHAPE_SHA256 =
   // Template merge. Both sides carried a digest of their own gate set; neither
   // describes the merged one. Recomputed from the merged config/ci/gates.json.
-  "5063586d799f51de94c0f0ddaf9b75e180825bba5051bc309550425013ea81ef";
+  // Task 11: recomputed again after FE-GATE-009 gained the
+  // TECH_LOG_STUDIO_ASSETS manual accessibility evidence artifact.
+  "3dda8421822eb094ceb06693ed8143cd9298947fa86681bbd941726a0d9674a9";
 
 function canonicalGateShapeSha256(gates: CiGateContract["gates"]): string {
   const normalized = gates.map(
@@ -486,8 +488,9 @@ function canonicalAuthorityBaselineFailures(contract: CiGateContract): string[]
     );
   }
   // Template merge. 126 product artifacts plus the two the template added.
-  if (contract.artifacts.length !== 128) {
-    failures.push(`artifact authority baseline must contain exactly 128 artifacts; received ${contract.artifacts.length}`);
+  // Task 11 added one more: the TECH_LOG_STUDIO_ASSETS manual a11y evidence file.
+  if (contract.artifacts.length !== 129) {
+    failures.push(`artifact authority baseline must contain exactly 129 artifacts; received ${contract.artifacts.length}`);
   }
   if (contract.stages.length !== 5) {
     failures.push(`stage authority baseline must contain exactly 5 stages; received ${contract.stages.length}`);