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/mod.rs

@@ -9,3 +9,4 @@ pub mod notifications;
 pub mod social;
 pub mod thoughts;
 pub mod users;
+pub mod well_known;

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" = [])))]

crates/presentation/src/handlers/well_known.rs

@@ -0,0 +1,20 @@
+use axum::{extract::State, http::header, response::IntoResponse};
+
+use crate::state::AppState;
+
+pub async fn host_meta(State(state): State<AppState>) -> impl IntoResponse {
+    let domain = url::Url::parse(&state.base_url)
+        .ok()
+        .and_then(|u| u.host_str().map(|s| s.to_string()))
+        .unwrap_or_default();
+    let body = format!(
+        r#"<?xml version="1.0" encoding="UTF-8"?>
+<XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
+  <Link rel="lrdd" template="https://{domain}/.well-known/webfinger?resource={{uri}}"/>
+</XRD>"#
+    );
+    (
+        [(header::CONTENT_TYPE, "application/xrd+xml; charset=utf-8")],
+        body,
+    )
+}

crates/presentation/src/routes.rs

@@ -135,5 +135,7 @@ pub fn router() -> Router<AppState> {
         )
         .route("/api-keys/{id}", delete(api_keys::delete_api_key_handler));
 
-    openapi::serve(api_routes).route("/media/{*path}", get(media::get_media))
+    openapi::serve(api_routes)
+        .route("/media/{*path}", get(media::get_media))
+        .route("/.well-known/host-meta", get(well_known::host_meta))
 }

crates/presentation/src/testing.rs

@@ -97,6 +97,9 @@ impl ActivityPubRepository for NoOpApRepo {
     ) -> Result<Option<ActorApUrls>, DomainError> {
         Ok(None)
     }
+    async fn sync_remote_actor_to_user(&self, _actor_ap_url: &str) -> Result<(), DomainError> {
+        Ok(())
+    }
 }
 
 pub struct NoOpMediaStore;