feat: prisma schema User + SyncRun + seed admin

Sets up Prisma 7 with SQLite (better-sqlite3 adapter), User and SyncRun models, migration, and admin seed account for mathieu.fort@gmail.com.

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

package.json

@@ -6,11 +6,17 @@
     "dev": "next dev",
     "build": "next build",
     "start": "next start",
-    "lint": "next lint"
+    "lint": "next lint",
+    "db:seed": "SEED_ADMIN_PASSWORD=admin123 ts-node --compiler-options '{\"module\":\"CommonJS\"}' prisma/seed.ts"
+  },
+  "prisma": {
+    "seed": "ts-node --compiler-options '{\"module\":\"CommonJS\"}' prisma/seed.ts"
   },
   "dependencies": {
+    "@prisma/adapter-better-sqlite3": "^7.8.0",
     "@prisma/client": "^7.8.0",
     "bcryptjs": "^3.0.3",
+    "better-sqlite3": "^12.10.0",
     "next": "14.2.35",
     "next-auth": "^4.24.14",
     "react": "^18",
@@ -32,6 +38,7 @@
     "prisma": "^7.8.0",
     "tailwindcss": "^3.4.1",
     "ts-jest": "^29.4.11",
+    "ts-node": "^10.9.2",
     "typescript": "^5"
   }
 }