security: clean repository without media files and sensitive data

- Removed area/ directory with 816MB of media files
- Removed sensitive FTP credentials from Git history
- Implemented .env.upload system for secure deployments
- Added comprehensive .gitignore for future protection

This commit represents a clean slate with all sensitive data removed.

backend/public/asset-manifest.json

@@ -0,0 +1,13 @@
+{
+  "files": {
+    "main.css": "/static/css/main.7b221a61.css",
+    "main.js": "/static/js/main.f30d7548.js",
+    "index.html": "/index.html",
+    "main.7b221a61.css.map": "/static/css/main.7b221a61.css.map",
+    "main.f30d7548.js.map": "/static/js/main.f30d7548.js.map"
+  },
+  "entrypoints": [
+    "static/css/main.7b221a61.css",
+    "static/js/main.f30d7548.js"
+  ]
+}