fix(career): exclude orphaned song_stats from star totals

Codex preflight: scans hide rather than delete stats of removed songs, so
stars now apply the same existing-song filter other stats surfaces use
(filename IN (SELECT filename FROM songs)).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

plugins/career/routes.py

@@ -70,8 +70,11 @@ def _stars():
     if db is None:
         return 0, {}
     thresholds = _state["content"]["star_accuracy_thresholds"]
+    # Existing-song filter: a scan hides (not deletes) stats of songs removed
+    # from the library, so orphaned rows must not keep counting toward stars.
     rows = db.conn.execute(
-        "SELECT filename, MAX(best_accuracy) FROM song_stats GROUP BY filename"
+        "SELECT filename, MAX(best_accuracy) FROM song_stats "
+        "WHERE filename IN (SELECT filename FROM songs) GROUP BY filename"
     ).fetchall()
     per_song = {}
     for filename, acc in rows:

tests/plugins/career/conftest.py

@@ -23,10 +23,15 @@ class FakeMetaDb:
                    filename TEXT, arrangement TEXT, best_accuracy REAL
                )"""
         )
+        self.conn.execute("CREATE TABLE songs (filename TEXT)")
 
-    def add(self, filename, arrangement, best_accuracy):
+    def add(self, filename, arrangement, best_accuracy, in_library=True):
         self.conn.execute("INSERT INTO song_stats VALUES (?, ?, ?)",
                           (filename, arrangement, best_accuracy))
+        if in_library:
+            self.conn.execute(
+                "INSERT INTO songs SELECT ? WHERE NOT EXISTS "
+                "(SELECT 1 FROM songs WHERE filename = ?)", (filename, filename))
         self.conn.commit()
 
 

tests/plugins/career/test_routes.py

@@ -42,6 +42,16 @@ def test_unlock_flags_follow_thresholds(client, meta_db):
     assert by_id["arena"]["unlocked"] is False
 
 
+def test_orphaned_stats_do_not_count(client, meta_db):
+    # A song removed from the library (stats row survives the scan) must not
+    # keep contributing stars.
+    meta_db.add("gone.feedpak", "guitar", 0.99, in_library=False)
+    meta_db.add("here.feedpak", "guitar", 0.99)
+    state = client.get("/api/plugins/career/state").json()
+    assert state["stars_total"] == 3
+    assert "gone.feedpak" not in state["stars_per_song"]
+
+
 def test_no_stats_still_serves_state(client):
     state = client.get("/api/plugins/career/state").json()
     assert state["stars_total"] == 0