fix(storyboard): deep-match capability gate values

[bokelley]

Summary

• support JSON-valued contains and not_contains capability predicates
• compare object entries structurally, independent of object key order
• cover the adcp.governance_enforcement.tasks[] signal-governance gate through the real storyboard runner

Unblocks adcontextprotocol/adcp#6590.

Validation

• npm run build
• node --test-timeout=60000 --test-force-exit --test test/lib/storyboard-capability-gate.test.js
• npm run typecheck
• npm run lint (0 errors; existing warnings only)

[aao-secretariat]

Ladon verdict: Approve

Approve.

Replaces reference-equality Array.includes with a structural deep-equal (capabilityValuesEqual) for storyboard contains/not_contains capability gates, correctly fixing object-valued declarations that could never match under identity comparison. Deep-equal handling is sound (order-sensitive arrays, key-order-insensitive objects, array-vs-object mismatch guarded). Type widening to CapabilityPredicateValue is additive and non-breaking; the patch changeset matches the bugfix impact (no removed/renamed exports, no required-param flips, no wire-shape change). Tests cover the new branches.

No critical, high, or medium findings. No high-risk paths, no gated paths, no author-team gate. Falls through to row 9.