fix(ap): protocol compliance — actor verification, on_unlike, Move, bto/bcc

- Add verify() to Accept/Reject (actor must match Follow target)
- Add verify() to Create/Update (actor must match attributedTo)
- Add verify() to Delete (actor domain must match object domain)
- Fix UpdateActivity passing wrapper id instead of object id to on_update
- Implement on_unlike (was no-op stub) — publishes LikeRemoved event
- BlockActivity now removes remote actor as follower, not just following
- Add MoveActivity (account migration) to InboxActivities enum
- Add bto/bcc fields to CreateActivity for blind DM support
- http_signature_compat(true) restricted to debug mode only
- Announce of non-local object logs debug instead of silent drop
- postgres-federation: get_followers/get_following_page/count_following
  now consistently filter by status='accepted'

crates/adapters/activitypub-base/src/federation.rs

@@ -33,7 +33,6 @@ impl ApFederationConfig {
                 .domain(&data.domain)
                 .app_data(data)
                 .debug(false)
-                .http_signature_compat(true)
                 .build()
                 .await?
         };