feat(14-01): rewrite database foundation from SQLite to PostgreSQL

- Replace all 13 sqliteTable definitions with pgTable (pg-core)
- Convert integer timestamps to native timestamp type with defaultNow()
- Convert real columns to doublePrecision, integer used to boolean
- Rewrite db connection to use postgres.js driver with DATABASE_URL
- Rewrite migrate.ts to use postgres-js migrator targeting drizzle-pg/
- Convert seed.ts to async
- Update drizzle.config.ts to postgresql dialect
- Install postgres and @electric-sql/pglite, remove better-sqlite3

package.json

@@ -21,12 +21,10 @@
 		"@tanstack/react-query-devtools": "^5.91.3",
 		"@tanstack/react-router-devtools": "^1.166.7",
 		"@tanstack/router-plugin": "^1.166.9",
-		"@types/better-sqlite3": "^7.6.13",
 		"@types/bun": "latest",
 		"@types/react": "^19.2.14",
 		"@types/react-dom": "^19.2.3",
 		"@vitejs/plugin-react": "^6.0.1",
-		"better-sqlite3": "^12.8.0",
 		"concurrently": "^9.1.2",
 		"drizzle-kit": "^0.31.9",
 		"vite": "^8.0.0"
@@ -35,6 +33,7 @@
 		"typescript": "^5.9.3"
 	},
 	"dependencies": {
+		"@electric-sql/pglite": "^0.4.3",
 		"@hono/zod-validator": "^0.7.6",
 		"@modelcontextprotocol/sdk": "^1.29.0",
 		"@tailwindcss/vite": "^4.2.1",
@@ -45,6 +44,7 @@
 		"framer-motion": "^12.38.0",
 		"hono": "^4.12.8",
 		"lucide-react": "^0.577.0",
+		"postgres": "^3.4.8",
 		"react": "^19.2.4",
 		"react-dom": "^19.2.4",
 		"recharts": "^3.8.0",