Rebuild atomcms-next foundation on Prisma (align to habbo-next reference)

Replace the superseded Drizzle monorepo scaffold with a single-app Prisma 7
data layer, mirroring the proven habbo-next approach to the shared Arcturus
emulator DB (introspect/conform only, idempotent SQL migrations via a custom
runner; never migrate-diff).

- prisma/schema.prisma: User, UsersCurrency (composite PK), Ban, WebsiteSetting
  mapped to AtomCMS's default.sql columns; client generated to src/generated/prisma
- src/lib/prisma.ts: PrismaMariaDb adapter singleton; src/env.ts zod env
- src/lib/services: siteSettings (cached setting() equivalent) + CurrencyType enum
- prisma/migrations + scripts/apply-migrations.ts: idempotent CMS-table runner

Verified: prisma generate OK, tsc --noEmit exit 0, vitest 6/6 pass.

package.json

@@ -5,18 +5,26 @@
   "engines": { "node": ">=22" },
   "packageManager": "[email protected]",
   "scripts": {
-    "build": "turbo run build",
-    "test": "turbo run test",
-    "typecheck": "turbo run typecheck"
+    "prisma:generate": "prisma generate",
+    "typecheck": "tsc --noEmit",
+    "test": "vitest run",
+    "db:migrate": "tsx scripts/apply-migrations.ts",
+    "db:migrate:status": "tsx scripts/apply-migrations.ts --status"
+  },
+  "dependencies": {
+    "@prisma/adapter-mariadb": "^7.8.0",
+    "@prisma/client": "^7.8.0",
+    "zod": "^3.24.0"
   },
   "devDependencies": {
-    "turbo": "^2.3.0",
-    "typescript": "^5.7.0",
+    "@types/node": "^22.10.0",
+    "dotenv": "^16.4.0",
+    "prisma": "^7.8.0",
     "tsx": "^4.19.0",
-    "vitest": "^2.1.0",
-    "@types/node": "^22.10.0"
+    "typescript": "^5.7.0",
+    "vitest": "^2.1.0"
   },
   "pnpm": {
-    "onlyBuiltDependencies": ["esbuild"]
+    "onlyBuiltDependencies": ["esbuild", "prisma", "@prisma/client", "@prisma/engines"]
   }
 }