feat(zones): profile-scoped groups, zone modes, sequence brightness

- Optional profile_id on groups; UI and API for shared vs profile-only groups\n- Zone content_kind (presets vs sequences); edit modal shows matching sections; devices via groups only\n- Server sequence playback folds zone brightness into preset wire b (per MAC where needed)\n- Related preset/sequence/audio/beat-route and client updates

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/models/test_sequence.py

@@ -26,7 +26,8 @@ def test_sequence():
     assert sequence["steps"] == []
     assert sequence["lanes"] == [[]]
     assert sequence.get("lanes_group_ids") == [[]]
-    assert sequence.get("advance_mode") == "time"
+    assert sequence.get("advance_mode") == "beats"
+    assert sequence.get("simulated_bpm") == 120
     assert sequence["step_duration_ms"] == 3000
     assert sequence["loop"] is True
     assert sequence.get("sequence_transition") == 500
@@ -42,6 +43,7 @@ def test_sequence():
         "step_duration_ms": 5000,
         "loop": True,
         "advance_mode": "beats",
+        "simulated_bpm": 128,
     }
     result = sequences.update(sequence_id, update_data)
     assert result is True
@@ -56,6 +58,7 @@ def test_sequence():
     assert len(updated["lanes"][0]) == 2
     assert updated["lanes"][0][0]["beats"] == 2
     assert updated.get("advance_mode") == "beats"
+    assert updated.get("simulated_bpm") == 128
     assert updated["step_duration_ms"] == 5000
     assert updated["loop"] is True