feat: add PostgreSQL config and dependencies

package.json

@@ -17,6 +17,7 @@
     "@discordjs/opus": "^0.10.0",
     "@discordjs/voice": "^0.19.1",
     "@snazzah/davey": "^0.1.10",
+    "@types/pg": "^8.20.0",
     "better-sqlite3": "^12.10.0",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.15.1",
@@ -27,6 +28,7 @@
     "helmet": "^8.1.0",
     "libsodium-wrappers": "^0.8.2",
     "p-retry": "^6.2.0",
+    "pg": "^8.20.0",
     "pino": "^9.4.0",
     "pino-http": "^11.0.0",
     "prism-media": "2.0.0-alpha.0",