Fail closed when QuoteHydrator TES or socialgraph lookup fails

[Pitchfork-and-Torch]

Bug

For You QuoteHydrator treats TES and socialgraph failure as "not a quote".

TES miss or Err was cached as quoted_tweet_id = None. Later VF, mute, and blocked-by never see the inner tweet. Following Night Owl already carries quoted_tweet_id on the search hit, so reverse-chron still VF-evaluates the quote.

Socialgraph check_blocked_by used unwrap_or_default(). Empty set => quoted_author_blocks_viewer = false. Following FollowingBlockedByHydrator returns Err for the batch on the same RPC failure.

• Entry: Phoenix QuoteHydrator (phoenix_candidate_pipeline.rs)
• Sink: should_drop_ancillary (needs Some quoted id), AuthorSocialgraphFilter quoted blocked-by
• Break: TES miss cached as no-quote; graph fail becomes not-blocked
• Viewer effect: quote of a VF-Drop / blocked author serves as a normal For You card; miss stays cached after TES recovers
• Twin: Following Night Owl keeps quote ids; FollowingBlockedByHydrator fail-closes graph errors

This is not PR 7 (mixer author graph filter). This is not PR 94 (core TES wiping retweet/reply ids). This is not PR 23 (mute quoted author when the id is present).

Fix

Do not cache TES lookup failure. Surface Err so update does not write a fake None. Fail the batch when socialgraph blocked-by errors, matching Following.

Genuine Ok(None) (not a quote) is still cached.

Tests

cargo: cannot run. Public dump has no Home Mixer manifest.