Merge views into Match, expand history, and polish the UI

- Match page now holds players/match info, turn stats with a turn
  picker, and the deck lists (My deck · Preview · Opponent); the Deck
  and Turn tabs are gone. Section heights are draggable and remembered.
- History: sortable, resizable columns; deck and commander columns;
  right-click to show only or hide games with a value, with filter
  chips; stats tiles (win rate overall, last 10/100, last 7 days,
  play/draw, average length and turns) that follow the filters.
  Commanders are backfilled for games recorded before they were stored.
- Deck panel shows copies per zone against the deck total (e.g. 2/5).
- Preview can be cleared with ✕, a click on the image, or Esc.
- Customize menu stays open while toggling; Arrange covers deck
  sections and turn stats together.
- Fix squeezed nav buttons and the header pushing controls off-screen.
- Fix known opponent cards being double-counted when also revealed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_history.py

@@ -65,3 +65,36 @@ def test_recorder_ignores_unfinished_match(tmp_path):
         t.handle(ev)
         rec.observe(ev, t)
     assert store.games() == []
+
+
+def test_old_database_is_upgraded_and_backfilled(tmp_path):
+    import sqlite3
+    path = tmp_path / "old.db"
+    store = HistoryStore(path)
+    import_log(FIXTURE, store, None)
+    # Simulate a database from before commanders were stored.
+    conn = sqlite3.connect(path)
+    conn.execute("UPDATE games SET my_commander = NULL, opp_commander = NULL")
+    conn.commit()
+    conn.close()
+
+    store = HistoryStore(path)
+    assert all(g.my_commander is None for g in store.games())
+    assert store.backfill_commanders(None) == 2
+    assert all(g.my_commander == "" and g.opp_commander == "" for g in store.games())  # not a Brawl match
+    assert store.backfill_commanders(None) == 0
+
+
+def test_schema_without_commander_columns_gets_them(tmp_path):
+    import sqlite3
+    path = tmp_path / "v1.db"
+    conn = sqlite3.connect(path)
+    conn.executescript("""CREATE TABLE games (match_id TEXT NOT NULL, game_number INTEGER NOT NULL,
+        started_ms INTEGER, ended_ms INTEGER, event_id TEXT, opponent TEXT, deck_name TEXT, on_play TEXT,
+        result TEXT, my_colors TEXT, opp_colors TEXT, turns INTEGER, best_of INTEGER,
+        PRIMARY KEY (match_id, game_number));
+        INSERT INTO games VALUES ('m1', 1, 1, 2, 'Ladder', 'Opp', 'Deck', 'me', 'Won', 'U', 'R', 5, 1);""")
+    conn.commit()
+    conn.close()
+    games = HistoryStore(path).games()
+    assert len(games) == 1 and games[0].deck_name == "Deck" and games[0].my_commander is None