fix(federation): fix 27 AP bugs, gaps, and inconsistencies

Round 1 — 18 bug fixes:
- remote likes/boosts now persist in engagement tables
- intern_remote_actor uses name@domain, expanded username to VARCHAR(255)
- PgRemoteActorRepository upsert/find now handles all fields
- update_following_status no longer a no-op, count_followers counts all
- accept/reject follow publishes event before DB mark (atomicity)
- fetch_outbox_page follows pagination via next links
- actor URL canonicalized to /users/{uuid}
- content_to_html escapes single quotes
- WebFinger accepts application/ld+json type
- try_from_ap accepts Article and Page object types
- feed SQL uses parameterized viewer UUID instead of format!
- content cap raised from 500 to 5000 chars
- also_known_as changed from Option<String> to Vec<String>
- connections fetch always triggers from page 1

Round 2 — 9 gap fixes:
- on_announce_removed handler deletes boost row on Undo(Announce)
- on_update handles Person/Service/Group actor profile updates
- sync_remote_actor_to_user syncs remote_actors → users on create/update
- FederationBlockPort: block_by_username sends Block activity to remote
- domain RemoteActor gains inbox_url, shared_inbox_url fields
- remote_actors attachment column (JSONB) with read/write
- .well-known/host-meta endpoint
- 256KB body limit on AP inbox routes
- outbox cleanup job (7-day retention, hourly sweep)

crates/presentation/src/handlers/social/mod.rs

@@ -119,7 +119,15 @@ pub async fn post_block(
     AuthUser(uid): AuthUser,
     Path(username): Path<String>,
 ) -> Result<StatusCode, ApiError> {
-    block_by_username(&*d.blocks, &*d.users, &*d.events, &uid, &username).await?;
+    block_by_username(
+        &*d.blocks,
+        &*d.users,
+        &*d.federation,
+        &*d.events,
+        &uid,
+        &username,
+    )
+    .await?;
     Ok(StatusCode::NO_CONTENT)
 }
 #[utoipa::path(delete, path = "/users/{username}/block", params(("username" = String, Path, description = "Username")), responses((status = 204, description = "Unblocked")), security(("bearer_auth" = [])))]
@@ -128,7 +136,15 @@ pub async fn delete_block(
     AuthUser(uid): AuthUser,
     Path(username): Path<String>,
 ) -> Result<StatusCode, ApiError> {
-    unblock_by_username(&*d.blocks, &*d.users, &*d.events, &uid, &username).await?;
+    unblock_by_username(
+        &*d.blocks,
+        &*d.users,
+        &*d.federation,
+        &*d.events,
+        &uid,
+        &username,
+    )
+    .await?;
     Ok(StatusCode::NO_CONTENT)
 }
 #[utoipa::path(put, path = "/users/me/top-friends", request_body = SetTopFriendsRequest, responses((status = 204, description = "Top friends updated")), security(("bearer_auth" = [])))]