feat: game importance factor in hype scoring

Adds calculate_game_importance() that boosts Priority for high-stakes
regular-season matchups based on season progress (sharp ramp after game
55), playoff bubble proximity (wildcard rank ~17-19 = max relevance),
and divisional/conference rivalry (1.4x/1.2x multipliers). Max bonus
150 pts applied to both LIVE and PRE games; playoff and FINAL games
are unaffected. Extends standings schema with division, conference,
games_played, and wildcard_sequence fields fetched from the NHL API.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/conftest.py

@@ -78,7 +78,8 @@ def flask_client(tmp_path, monkeypatch):
     conn = sqlite3.connect(str(db_path))
     conn.execute(
         "CREATE TABLE standings "
-        "(team_common_name TEXT, league_sequence INTEGER, league_l10_sequence INTEGER)"
+        "(team_common_name TEXT, league_sequence INTEGER, league_l10_sequence INTEGER, "
+        "division_abbrev TEXT, conference_abbrev TEXT, games_played INTEGER, wildcard_sequence INTEGER)"
     )
     conn.commit()
     conn.close()