Remove obsolete scripts and configuration files for self-hosting and database migrations

- Deleted `pnpm-workspace.yaml` as it is no longer needed.
- Removed `apply-migrations.sh` script that handled database migrations.
- Eliminated `generate-full-stack-env.mjs` script for environment variable generation.
- Deleted `selfhost-backup.sh` script for creating backups of the self-hosted environment.
- Removed `selfhost-doctor.sh` script for health checks of the self-hosted services.
- Deleted `selfhost-restore.sh` script for restoring backups in the self-hosted environment.

app/login/actions.ts

@@ -34,7 +34,7 @@ export async function signup(formData: FormData) {
   if (!setupState.available) {
     redirect(
       `/login?error=true&message=${encodeURIComponent(
-        'Kayıt kapalı. Bu self-host kurulumunda ilk admin hesabı zaten oluşturulmuş.',
+        'Kayıt kapalı. Bu Neta kurulumunda ilk admin hesabı zaten oluşturulmuş.',
       )}`,
     )
   }