feat: add feed

internal/repository/user_repo.go

@@ -379,6 +379,47 @@ func (r *UserRepo) Search(ctx context.Context, q string, limit, offset int) ([]m
 	return out, total, rows.Err()
 }
 
+// RecentlyJoined returns up to `limit` users who registered on/after `since`,
+// newest first, as a discovery list for the feed's "new on the platform"
+// strip. Excludes the viewer, anyone the viewer already has a follow edge with
+// (pending or accepted), and anyone involved in a block either direction — so
+// every suggestion is a fresh account the viewer can actually follow.
+func (r *UserRepo) RecentlyJoined(ctx context.Context, viewerID string, since time.Time, limit int) ([]model.UserSummary, error) {
+	if limit <= 0 || limit > 20 {
+		limit = 5
+	}
+	const q = `
+		SELECT u.id, u.handle, u.name, u.avatar_url
+		FROM users u
+		WHERE u.created_at >= $2
+		  AND u.id <> $1
+		  AND NOT EXISTS (
+		      SELECT 1 FROM follows f
+		      WHERE f.follower_id = $1 AND f.following_id = u.id
+		  )
+		  AND NOT EXISTS (
+		      SELECT 1 FROM user_blocks b
+		      WHERE (b.blocker_id = $1 AND b.blocked_id = u.id)
+		         OR (b.blocker_id = u.id AND b.blocked_id = $1)
+		  )
+		ORDER BY u.created_at DESC
+		LIMIT $3`
+	rows, err := r.pg.Pool.Query(ctx, q, viewerID, since, limit)
+	if err != nil {
+		return nil, fmt.Errorf("recently joined: %w", err)
+	}
+	defer rows.Close()
+	out := []model.UserSummary{}
+	for rows.Next() {
+		var u model.UserSummary
+		if err := rows.Scan(&u.ID, &u.Handle, &u.Name, &u.AvatarURL); err != nil {
+			return nil, fmt.Errorf("scan recently joined: %w", err)
+		}
+		out = append(out, u)
+	}
+	return out, rows.Err()
+}
+
 // GetReadingPrefs returns the raw JSONB bytes for the user's reading
 // prefs (empty object when never set). The frontend owns the shape, so
 // we round-trip the payload verbatim — no server-side schema enforced.