* feat(router): expose route graph manifest read model
The App Router graph now exposes root-boundary identity and a stable RouteManifest read model instead of leaving these facts implicit inside per-route arrays. Future #726 planner and compatibility work needs a semantic lookup surface for routes, layouts, pages, templates, slots, and root boundaries before it can stop reading meaning from transport keys.
This adds RootBoundaryId, graphVersion, StaticSegmentGraph maps, and fail-fast invariant checks for mismatched layout/template positions while preserving the existing routes array for current callers.
* chore: retrigger ci
* feat(server): add disabled cache proof model
Route-scoped cache work currently lacks a typed proof boundary for representing render observations, variants, and breaker fallback decisions. That makes future cache reuse work easy to wire before proof completeness is explicit.
The missing invariant is that cache proof data must be canonical, redacted, bounded, and incapable of authorizing runtime reuse while the model is disabled.
Add a v0 cache proof model with RenderObservation, CacheVariant, BoundaryOutcomeCompatibility, variant budgets, and breaker fallbacks. The disabled decision always returns canReuse false, and tests cover canonical redacted dimensions, budget breaker paths, negative request API proof completeness, exact boundary outcome matching, and the disabled reuse gate.
Refs #726
* fix(server): use distinct invalid cache budget code
Invalid cache proof budget fields currently report the route variant ceiling reason code, even when the failing field is unrelated to route cardinality.
That conflates malformed configuration with an actual per-route variant ceiling breach.
Add CP_INVALID_VARIANT_BUDGET for invalid budget fields while leaving CP_ROUTE_VARIANT_CEILING_EXCEEDED for real route variant count failures. Cover maxEncodedLength as the regression case.
Refs #726
* fix(server): harden disabled cache proof invariants
Disabled cache proof variants currently collapse null and empty-string output scope fields into the same encoded value. That makes a future empty-string field addition able to collide silently with absent values.
The matcher also leaves two defensive contracts implicit: breaker fallback detection depends on the generic kind field, and the private boundary matcher would treat unknown as a match if called directly.
Preserve null through JSON output encoding, use the fallback-specific code field for the internal breaker guard, and make unknown outcomes non-matching at the matcher level. Add coverage for null versus empty-string scope keys and for missing request API observations not counting as negative proof.
Refs #726