Closes the real hashtag gap. Verified the upload modal's existing NIP-71 hashtag
editor (Nip71FormManager → nip71.hashtags → buildNip71MetadataTags) ALREADY emits
`t` tags on the 30078, which bitvid's feed scoring already reads — so publish+feed
hashtags work today. The gap was the 34235 mirror reading only `video.hashtags`
(empty for form-authored videos).
buildNip71MirrorEvent now resolves hashtags from whichever source is present —
video.hashtags, video.nip71.hashtags, or the raw `t` tags on video.tags — deduped,
lowercased, with bitvid's internal "video" topic tag dropped. So a shared video
stays categorized on Nostube/Amethyst regardless of how its tags were authored.
(The earlier content.hashtags builder path from a1bf7b15 stays as a harmless
secondary input; the form/t-tag path is the one users actually exercise.)
tests/nip71-mirror.test.mjs: hashtags sourced from nip71.hashtags; from raw t tags
with the 'video' topic dropped + deduped. Mutation-verified.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
