chore(frontend): consolidate wrangler config to jsonc

- Remove redundant wrangler.toml (old Pages config)
- Rename worker from enchun-frontend to website-enchun-mgr
- Keep wrangler.jsonc as single source of truth

apps/frontend/wrangler.jsonc

@@ -1,6 +1,6 @@
 {
     "$schema": "./node_modules/wrangler/config-schema.json",
-    "name": "enchun-frontend",
+    "name": "website-enchun-mgr",
     "main": "./dist/_worker.js/index.js",
     "compatibility_date": "2025-01-19",
     "compatibility_flags": [
@@ -14,7 +14,7 @@
     },
     "env": {
         "production": {
-            "name": "enchun-frontend-production",
+            "name": "website-enchun-mgr-production",
             "vars": {
                 "PAYLOAD_CMS_URL": "https://enchun-admin.anlstudio.cc"
             }