refactor(domain): remove public_key/private_key from User model — managed by federation adapter

crates/adapters/postgres/src/feed.rs

@@ -58,8 +58,6 @@ struct FeedRow {
     author_local: bool,
     u_ap_id: Option<String>,
     inbox_url: Option<String>,
-    public_key: Option<String>,
-    private_key: Option<String>,
     author_created_at: DateTime<Utc>,
     author_updated_at: DateTime<Utc>,
     like_count: i64,
@@ -87,7 +85,6 @@ fn feed_select(viewer: Option<uuid::Uuid>) -> String {
         u.id AS author_id, u.username, u.email, u.password_hash,
         u.display_name, u.bio, u.avatar_url, u.header_url, u.custom_css,
         u.local AS author_local, u.ap_id AS u_ap_id, u.inbox_url,
-        u.public_key, u.private_key,
         u.created_at AS author_created_at, u.updated_at AS author_updated_at,
         (SELECT COUNT(*) FROM likes l WHERE l.thought_id=t.id) AS like_count,
         (SELECT COUNT(*) FROM boosts b WHERE b.thought_id=t.id) AS boost_count,
@@ -125,8 +122,6 @@ fn row_to_entry(r: FeedRow) -> FeedEntry {
         local: r.author_local,
         ap_id: r.u_ap_id,
         inbox_url: r.inbox_url,
-        public_key: r.public_key,
-        private_key: r.private_key,
         created_at: r.author_created_at,
         updated_at: r.author_updated_at,
     };