T15-01 Add Playwright authentication fallback and storage-state refresh

[edithatogo]

Parent: #468

Implement T15-01: Cloudflare/403 challenge detection, explicit Playwright browser fallback for read-only requests, secure local storage-state recording, CLI refresh workflow, tests, documentation, and Conductor traceability.

[edithatogo]

Reopened conservatively. Archived implementation evidence remains valid; #533 is the verification continuation required before this track closes.