Fetch OON retweet originals at TimelineHomeRecommendations

[Pitchfork-and-Torch]

Bug

For You VF always fetches retweeted_tweet_id at TimelineHome, even when the wrapper is out-of-network. Quoted ids already go to TimelineHomeRecommendations.

OON-only Drop rules (NSFW_HIGH_PRECISION, DO_NOT_AMPLIFY, spam-high-recall, ...) are Interstitial on Home and Drop on Recs. should_drop_ancillary only drops Action::Drop. AncillaryVFFilter then keeps the OON retweet.

• Entry: VFCandidateHydrator pushes every retweeted_tweet_id onto in_network_ids
• Sink: AncillaryVFFilter
• Break: OON retweet original never sees Recs Drop
• Viewer effect: For You shows an OON retweet of a post that Recs would hard-drop
• Twin: quoted_tweet_id is already on the Recs vec

This is not PR 55 (dual-role merge of the same id as primary and ancestor). This is not PR 90. This is not the Following hydrator (that is a separate PR). In-network retweets stay on Home.

Fix

If the wrapper is in-network, keep the original on Home. If the wrapper is OON, fetch the original at Recs.

Tests

• OON wrapper, original Recs Drop / Home Interstitial -> drop_ancillary_posts = true; original fetched only at Recs
• In-network wrapper -> original stays on Home; ancillary not dropped on Interstitial
• Quoted id still Recs (no regression)

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

[Pitchfork-and-Torch]

Closing: not a serving bug on the wired Phoenix path. OONRetweetReplyFilter already drops in_network==false retweets before VF, so retweet originals never reach VFCandidateHydrator as OON wrappers. Following quotes/ancestors remain the live hole (PR 115).