Deleting a message on the watched channel now deletes the posts it
produced. Making that possible reshapes how a message reaches an output:
- OutputInterface takes an output.Post and returns an output.Ref, the
identifier the platform gave the new post (tweet ID for X, URI and
CID for bluesky). It also gained Delete(Ref).
- The discord package no longer forwards raw MessageCreate values but
a discord.Event carrying the kind of change, so the MessageDelete
handler can use the same channel. Deleted messages arrive without an
author, so only the channel ID can be filtered on.
- The new store package remembers Discord message ID -> per output Ref.
Set POST_STORE to a path to keep that mapping across restarts;
without it the mapping is memory only and a restart makes older
messages undeletable. It holds the most recent 1000 messages.
main.go grows a distributor type to hold the outputs and the store
rather than threading them through the event loop.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
