fix(nginx): align id and service name with folder name

- id: nginx-custom -> nginx (must match folder name for Runtipi discovery)
- tipiVersion: 1 -> tipi_version: 2 (correct key name and version)
- Removed min_tipi_version and $schema fields
- Service name: nginx-custom -> nginx

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

apps/nginx/config.json

@@ -1,16 +1,14 @@
 {
-  "$schema": "https://schemas.runtipi.io/config.json",
-  "name": "Nginx Custom",
-  "id": "nginx-custom",
+  "name": "Nginx",
+  "id": "nginx",
   "available": true,
   "short_desc": "Serveur web Nginx avec configuration personnalisable",
   "author": "Nginx Inc.",
   "port": 8080,
   "exposable": true,
   "dynamic_config": true,
-  "min_tipi_version": "4.5.0",
   "version": "1.0.0",
-  "tipiVersion": 1,
+  "tipi_version": 2,
   "categories": ["utilities", "network"],
   "description": "Nginx est un serveur web haute performance avec des volumes montés pour la configuration et le contenu des sites.",
   "website": "https://nginx.org",

apps/nginx/docker-compose.json

@@ -1,9 +1,7 @@
 {
-  "schemaVersion": 2,
-  "$schema": "https://schemas.runtipi.io/dynamic-compose.json",
   "services": [
     {
-      "name": "nginx-custom",
+      "name": "nginx",
       "image": "nginx:latest",
       "isMain": true,
       "internalPort": 80,