phase-8g: add sqllite.

package.json

@@ -25,11 +25,13 @@
     "@anthropic-ai/sdk": "^0.100.1",
     "@fastify/cors": "^11.2.0",
     "@fastify/rate-limit": "^10.2.1",
+    "better-sqlite3": "^11.10.0",
     "dotenv": "^16.0.0",
     "fastify": "^5.8.5",
     "yahoo-finance2": "^3.15.2"
   },
   "devDependencies": {
+    "@types/better-sqlite3": "^7.6.13",
     "@types/node": "^22.0.0",
     "@typescript-eslint/eslint-plugin": "^7.0.0",
     "@typescript-eslint/parser": "^7.0.0",