docs: audit For You feed algo <-> lists wiring (read-only, gaps + fix order)

Traced registerForYouFeed/buildForYouFeedRuntime + feedEngine. Confirms hashtag
prefs, blocks, watch-history suppression, and moderation DO drive For You. Gaps:
G1 follows have zero effect on For You; G2 chronological not relevance-ranked;
G3 interest filter is binary/exclusive; G4 watch-topic affinity unused; G5 no
blending. No code changed.

docs/README.md

@@ -7,6 +7,7 @@ Welcome to the bitvid documentation. This directory contains detailed architectu
 - **[Application Coordinators](./app-coordinators.md)**: Overview of the coordinator pattern used to manage app-wide state and services.
 - **[Data-Flow Refactor — Dev Plan & Spec](./architecture-refactor.md)**: The incremental plan to put all subsystems on a shared, governed relay/data foundation (SubscriptionManager, stores, unidirectional flow).
 - **[Known Bugs (deferred)](./KNOWN_BUGS.md)**: Confirmed defects/limitations found during the refactor, queued to fix later.
+- **[Feed Algorithm ↔ Lists Audit](./feed-algo-audit.md)**: Read-only audit of whether the For You feed is actually driven by the user's follows/hashtags/watch-history, with the gaps and a fix order.
 - **[Authentication Architecture](./auth-architecture.md)**: How session management, login flows, and signer integration work.
 - **[Feed Engine](./feed-engine.md)**: The pipeline for fetching, filtering, scoring, and sorting video feeds.
 - **[Playback & Fallback](./playback-fallback.md)**: The URL-first playback strategy with WebTorrent fallback orchestration.