feat(ap): ActivityPub spec compliance and profile completeness

Phase 1 — spec compliance:
- Add AS_PUBLIC constant; add to/cc fields to CreateActivity, DeleteActivity,
  UpdateActivity, AddActivity; populate on all broadcast call sites
- Add @context to outbox CreateActivity items
- Set manuallyApprovesFollowers: true to match actual Pending follow flow
- Gate PermissiveVerifier behind FEDERATION_DEBUG env var
- Add updated timestamp to Person actor JSON
- Improve actor update delivery logging

Phase 2a Batch 1 — AP layer:
- Add /inbox shared inbox route; add endpoints.sharedInbox to Person
- Paginate followers and following collections (20/page, OrderedCollectionPage)

Phase 2a Batch 2 — profile completeness:
- DB migrations: banner_path, also_known_as columns; user_profile_fields table
- ProfileField value object; UserProfileFieldsRepository port
- Banner image upload (stored via image-converter, surfaced as image in Person)
- alsoKnownAs field in Person (account migration support)
- Custom profile fields (up to 4 PropertyValue attachments in Person)
- Profile settings UI: banner preview/upload, alsoKnownAs input, fields form
- PUT /api/v1/profile/fields API endpoint

crates/adapters/sqlite/src/tests/users.rs

@@ -6,7 +6,7 @@ use sqlx::SqlitePool;
 async fn setup() -> (SqlitePool, SqliteUserRepository) {
     let pool = SqlitePool::connect(":memory:").await.unwrap();
     sqlx::query(
-        "CREATE TABLE users (id TEXT PRIMARY KEY, email TEXT NOT NULL UNIQUE, username TEXT NOT NULL UNIQUE, password_hash TEXT NOT NULL, created_at TEXT NOT NULL, role TEXT NOT NULL DEFAULT 'standard', bio TEXT, avatar_path TEXT)"
+        "CREATE TABLE users (id TEXT PRIMARY KEY, email TEXT NOT NULL UNIQUE, username TEXT NOT NULL UNIQUE, password_hash TEXT NOT NULL, created_at TEXT NOT NULL, role TEXT NOT NULL DEFAULT 'standard', bio TEXT, avatar_path TEXT, banner_path TEXT, also_known_as TEXT)"
     )
     .execute(&pool)
     .await
@@ -61,6 +61,8 @@ async fn update_profile_persists_bio_and_avatar() {
         user.id(),
         Some("My biography".to_string()),
         Some("avatars/user1".to_string()),
+        None,
+        None,
     )
     .await
     .unwrap();
@@ -80,10 +82,10 @@ async fn update_profile_clears_fields_with_none() {
         UserRole::Standard,
     );
     repo.save(&user).await.unwrap();
-    repo.update_profile(user.id(), Some("bio".to_string()), Some("path".to_string()))
+    repo.update_profile(user.id(), Some("bio".to_string()), Some("path".to_string()), None, None)
         .await
         .unwrap();
-    repo.update_profile(user.id(), None, None).await.unwrap();
+    repo.update_profile(user.id(), None, None, None, None).await.unwrap();
 
     let found = repo.find_by_id(user.id()).await.unwrap().unwrap();
     assert_eq!(found.bio(), None);