feat: behavioral compliance validations for storyboards

[bokelley]

Summary

Closes #497. Storyboard validations were mostly schema-only — agents could skip brand resolution, ignore property lists, or bypass content standards and still pass existing tests. This adds behavioral compliance checks and fixes request builder inconsistencies.

Storyboard validations:

• Brand rights: verify resolved identity data (brand_id match, names present), reject invalid brand IDs, validate creative approval decisions, enforce expired campaigns and nonexistent grants
• Property governance: assert compliant: true/false delivery verdicts, add enforcement phase with authorized and unauthorized publisher tests, explicit context_outputs for property_list_id, reorder delete after validation phases
• Content standards: assert calibration verdict, test must-rule violations (verdict: fail), test policy version changes with re-calibration, strengthen delivery validation checks

Request builder fixes:

• get_brand_identity / get_rights: respect sample_request.brand_id instead of always defaulting to test.example
• All property list builders (get, update, list, delete): pass brand consistently — fixes session key mismatch where create used one brand but subsequent operations used default

MCP Tasks error recovery:

• Recover adcpError content from SDK error events by fetching task result (JSON-parsed, not string-matched)

Test plan

• All tests pass (2,972 pass, 0 fail)
• All CI checks green (12/12)
• Code review: Must Fix items addressed (phase ordering, JSON parsing)
• Security review: clean — no secrets, injection vectors, or unsafe domains

🤖 Generated with Claude Code

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