feat: enforce runtime authorization - #122

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only still-valid issues, skip the rest with a brief reason, keep changes
minimal, and validate.

Inline comments:
In `@internal/core/service/reference/pagination.go`:
- Around line 124-142: In ListWhere, evaluate retain for every row that matches
query before applying pagination: move the cursor condition after retain returns
true, while preserving immediate error propagation and skipping rejected rows.
Only run afterCursor for retained rows, then append eligible rows to candidates.

In `@internal/core/service/referenceauthorization/service.go`:
- Around line 362-364: Update GetOperation and authorizeResource to convert
reference.ErrNotFound into ErrDenied before returning errors on
read/authorization paths, while preserving all other errors unchanged.
- Around line 431-435: Update referenceauthorization.mutate’s replay handling so
an expired reference replay is distinguished from a genuine admission replay
mismatch before returning ErrUnavailable. Reconcile the existing
service.requests mapping with the reference Service replay window; when the
reference mutation issues a new OperationID after expiry, replace the stale
mapping and record the corresponding admission so NewPlan and
WithExecutionAuthorization can use it, while preserving the mismatch error for
active conflicting replays.
- Line 352: Update the exported method documentation for the method containing
the effect() call to state that effect must not call back into the same Service,
because it executes while the Service mutex is held and such calls can deadlock.

In `@test/contract/testdata/reference-server-v1alpha1.golden.json`:
- Line 113: Update both replacement operationId values in the golden reference
data so they consistently match the operation ID identified by the location
header and response body, preserving receipt/replay consistency.

---

Outside diff comments:
In `@docs/architecture/0009-deterministic-hierarchical-authorization.md`:
- Around line 102-103: Update the deferred resolver list in the architecture
document to remove Operation and its operation.list/operation.get unavailability
claim, while retaining Plan and resource-anchored Audit as unavailable until
issue `#24`. Keep the later statement about the completed Operation resolver
consistent.

In `@docs/security/threat-model.md`:
- Line 34: Update the “Developer and contract-test profile” security-status row
to replace “action-gated reference HTTP” with loopback API and process-local
execution enforcing retained PolicySet authorization, and change the deferred
limitations to production OIDC and durable policy enforcement only; preserve the
other status claims.

---

Nitpick comments:
In `@internal/core/domain/authorization/authorization_test.go`:
- Line 634: The “provider environment substitution” test currently references a
provider ID that is not retained by newHierarchyFixture, so it exercises
provider lookup failure instead of the environment-mismatch path. Add or retain
a provider connection belonging to testEnvironmentB in newHierarchyFixture, then
update this test case to use that provider’s ID while preserving the expected
mismatch behavior.

In `@internal/core/service/referenceauthorization/service_test.go`:
- Around line 461-465: Add a deterministic synchronization seam in the
ReplaceMembers concurrency test to confirm it reaches service.mu acquisition
while the execution callback remains blocked. Assert revocation has not
completed before releasing release, then release the callback and await both
revocationResult and executionResult; avoid sleeps and timeouts, and ensure the
assertion would fail if ReplaceMembers did not acquire service.mu.

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