feat: Phase 1 — core game loop complete

New endpoints:
- GET  /cards/:card_id       single card lookup
- POST /packs/buy            purchase pack with coins
- POST /objectives/claim     claim completed objective reward
- GET  /matches              match history (limit/mode query params)
- GET  /sbc/:sbc_id          single SBC lookup

Card pool expanded:
- Bronze: 11 → 30 cards (19 nations)
- Silver: 0 → 20 cards (20 nations)
- Rare Gold: 0 → 10 cards (10 nations)

SBC pool expanded:
- Added 5 new SBCs (tri_nations, silver_to_gold, league_loyalty,
  african_stars, gold_standard)

Infrastructure:
- SQLite WAL mode enabled on pool init
- Foreign key enforcement enabled

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

data/sbcs/advanced_sbcs.json

@@ -0,0 +1,102 @@
+[
+  {
+    "id": "sbc_tri_nations",
+    "name": "Tri-Nations",
+    "description": "Field 11 players featuring at least one Brazilian, one Argentinian, and one Nigerian.",
+    "requirements": {
+      "squad_size": 11,
+      "min_overall": 60,
+      "max_overall": null,
+      "min_chemistry": null,
+      "required_leagues": [],
+      "required_nations": ["Brazil", "Argentina", "Nigeria"],
+      "required_clubs": [],
+      "min_players_from_same_league": null,
+      "min_players_from_same_nation": null,
+      "min_players_from_same_club": null
+    },
+    "reward": { "coins": 2500, "xp": 300, "pack_id": "silver_pack" },
+    "expires_at": null,
+    "repeatable": false
+  },
+  {
+    "id": "sbc_silver_to_gold",
+    "name": "Silver to Gold",
+    "description": "Submit 11 silver-quality players (average overall 68+) for a gold pack.",
+    "requirements": {
+      "squad_size": 11,
+      "min_overall": 68,
+      "max_overall": 74,
+      "min_chemistry": null,
+      "required_leagues": [],
+      "required_nations": [],
+      "required_clubs": [],
+      "min_players_from_same_league": null,
+      "min_players_from_same_nation": null,
+      "min_players_from_same_club": null
+    },
+    "reward": { "coins": 0, "xp": 350, "pack_id": "gold_pack" },
+    "expires_at": null,
+    "repeatable": true
+  },
+  {
+    "id": "sbc_league_loyalty",
+    "name": "League Loyalty",
+    "description": "Build a squad where at least 8 players share the same league.",
+    "requirements": {
+      "squad_size": 11,
+      "min_overall": 62,
+      "max_overall": null,
+      "min_chemistry": null,
+      "required_leagues": [],
+      "required_nations": [],
+      "required_clubs": [],
+      "min_players_from_same_league": 8,
+      "min_players_from_same_nation": null,
+      "min_players_from_same_club": null
+    },
+    "reward": { "coins": 1500, "xp": 200, "pack_id": null },
+    "expires_at": null,
+    "repeatable": true
+  },
+  {
+    "id": "sbc_african_stars",
+    "name": "African Stars",
+    "description": "Celebrate African football — need at least one player from Ghana and one from Senegal.",
+    "requirements": {
+      "squad_size": 11,
+      "min_overall": 60,
+      "max_overall": null,
+      "min_chemistry": null,
+      "required_leagues": [],
+      "required_nations": ["Ghana", "Senegal"],
+      "required_clubs": [],
+      "min_players_from_same_league": null,
+      "min_players_from_same_nation": null,
+      "min_players_from_same_club": null
+    },
+    "reward": { "coins": 1000, "xp": 150, "pack_id": "bronze_pack" },
+    "expires_at": null,
+    "repeatable": false
+  },
+  {
+    "id": "sbc_gold_standard",
+    "name": "Gold Standard",
+    "description": "Submit 11 high-quality players with an average overall of 76+.",
+    "requirements": {
+      "squad_size": 11,
+      "min_overall": 76,
+      "max_overall": null,
+      "min_chemistry": null,
+      "required_leagues": [],
+      "required_nations": [],
+      "required_clubs": [],
+      "min_players_from_same_league": null,
+      "min_players_from_same_nation": null,
+      "min_players_from_same_club": null
+    },
+    "reward": { "coins": 3000, "xp": 500, "pack_id": "rare_gold_pack" },
+    "expires_at": null,
+    "repeatable": false
+  }
+]