[ACT-09] Compare a false-positive and real Playbook drift finding

[EmersonBraun]

Goal

Contribute two fixtures: one finding that looks like drift but is a false positive, and one finding that is real drift. Include the pattern version and source evidence for both.

Evidence

• Human guide: docs/agents/ecosystem-playbook-alignment-auditor.md
• Agent test: registry/ecosystem-playbook-alignment-auditor/agent.test.ts

Acceptance criteria

• Each fixture has an expected result.
• Source pattern and version are recorded.
• The auditor output remains review input, not an automatic compliance decision.
• Both cases pass targeted tests.

Human gate

A standards maintainer must verify the pattern version and evidence.