Promote APP_LINKS.md from a deferred design note into an implementation spec
matching the website `feat/mobile-app-links` and android `feat/app-links`
branches: the server-side `/.well-known/assetlinks.json` route + `mobile_app_links_enabled`
toggle + additive redirect-allowlist entry, and the app-side `autoVerify`
intent-filter driven by a build-time `appLinkHost` (a single multi-tenant APK
cannot autoVerify open-ended shard domains, so App Links are a white-label /
first-party build opt-in; the custom scheme stays the permanent fallback).
Update PLAN.md §9 (M9 follow-up) and the §14 open item, and the redirect-URI
allowlist section of website/BACKEND_DESIGN.md.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NgyHnrNa8WwG3doxvxjuCr
Record the plan before coding: native Android "Sign in with Google/Discord"
via a Mobile SSO Authorization Bridge that extends the existing /auth/sso/*
redirect flow and terminates in the existing mobile bearer tokens.
- BACKEND_DESIGN.md: mobile_auth_sessions / mobile_auth_codes schema, the
/auth/mobile/sso/{start,exchange} contract, the two PKCE layers, state/CSRF,
exact-match redirect-URI allowlist, TOTP parity, and the documented
revocation-latency window.
- android/PLAN.md: promote §4.2's "possible later enhancement" to milestone M9
(backend-first, mirroring M7); status note.
- android/APP_LINKS.md: new architecture note on the per-shard assetlinks.json
/ pairing multi-tenancy question (App Links deferred; custom scheme only now).
Co-Authored-By: Claude <noreply@anthropic.com>
