chore: establish v3 GA readiness control room

[aerovulpe]

Summary

• add the canonical V3 GA plan, dynamic tracker, evidence register, decision log, and complete live issue/PR triage
• freeze the normalized RC3 public API and enforce reviewed drift in aggregate and pull-request verification
• apply the approved Node 22.14+ floor and add repeatable machine-readable triage capture
• preserve the GA hold while private security work is paused and route issue audio does not responsive on desktop mode #550 into GA-017

Verification

• npm run verify
• explicit Prettier check for all added control-room files and scripts
• tracker/link integrity check: 17 findings, 18 gates, 12 evidence records, 8 decisions, 8 tasks
• live triage reconciliation: 78 issues, 14 pull requests, zero missing or stale rows

Refs #580

[aerovulpe]

Repository controls are now active: verify is required, stale reviews dismiss on push, last-push approval and conversation resolution are required, admins are enforced, and npm-release requires @antoine92190 with self-review prevention. Auto-merge is enabled but will not bypass your review.