chore(db): add db:migrate script and pending-migration warning

README.md

@@ -70,11 +70,29 @@ Open http://localhost:3000 and sign in with the seeded admin account:
 admin@datashield.local / ChangeMe123!
 ```
 
+### Switching machines / after `git pull`
+
+The Prisma client is regenerated automatically on `npm install` (`postinstall`).
+The database is **not** migrated automatically: `npm run dev` only *warns* if
+migrations are pending (it never applies them on boot). After pulling changes
+that add a migration, apply it explicitly before running the app:
+
+```bash
+npm run db:migrate   # prisma migrate deploy, applies pending migrations
+```
+
+When you edit `prisma/schema.prisma` yourself, create the migration instead:
+
+```bash
+npx prisma migrate dev --name <change>
+```
+
 ### Database commands
 
 - `npm run db:init` starts a Postgres container (`compose.yml`), applies all
   migrations and seeds demo data (breaches, employees, alerts).
 - `npm run db:up` / `npm run db:down` start and stop the container.
+- `npm run db:migrate` applies pending migrations to the current database.
 - `npm run seed:dev` reseeds the demo data; `npm run seed` seeds only the admin.
 
 No Docker? Point `DATABASE_URL` at your own PostgreSQL, then run

package.json

@@ -14,6 +14,7 @@
   "author": "Melvin PETIT (WhiteMuush)",
   "type": "module",
   "scripts": {
+    "predev": "prisma migrate status || echo '\\n[!] Pending migrations or DB unreachable. If the app errors on a missing table, run: npm run db:migrate\\n'",
     "dev": "next dev",
     "build": "next build",
     "start": "next start",
@@ -23,6 +24,7 @@
     "db:up": "docker compose up -d db",
     "db:down": "docker compose down",
     "db:init": "sh scripts/db-init.sh",
+    "db:migrate": "prisma migrate deploy",
     "postinstall": "prisma generate",
     "prepare": "sh .githooks/install.sh",
     "seed:dev": "dotenv -e .env.local -- tsx prisma/seed.dev.ts"