Fix demo site auto-enhancement and content persistence

- Restructure demo directory from test-sites/ to demos/ with flattened layout
- Add auto-enhancement on server startup for all sites with auto_enhance: true
- Fix inconsistent content ID generation that prevented dan-eden-portfolio content persistence
- Update server configuration to enhance from source to separate output directories
- Remove manual enhancement from justfile in favor of automatic server enhancement
- Clean up legacy test files and unused restore command
- Update build system to use CDN endpoint instead of file copying

insertr.yaml

@@ -12,31 +12,31 @@ database:
 server:
   port: 8080            # HTTP API server port
   sites:                # Registered sites for file-based enhancement
-    - site_id: "demo"
-      path: "./test-sites/demo-site_enhanced"
+    - site_id: "default"
+      path: "./demos/default_enhanced"
+      source_path: "./demos/default"
       domain: "localhost:3000"
       auto_enhance: true
-      backup_originals: true
     - site_id: "simple"
-      path: "./test-sites/simple/test-simple_enhanced"
+      path: "./demos/simple_enhanced"
+      source_path: "./demos/simple"
       domain: "localhost:3000"
       auto_enhance: true
-      backup_originals: true
-    - site_id: "dan-eden"
-      path: "./test-sites/simple/dan-eden-portfolio_enhanced"
+    - site_id: "dan-eden-portfolio"
+      path: "./demos/dan-eden-portfolio_enhanced"
+      source_path: "./demos/dan-eden-portfolio"
       domain: "localhost:3000"
       auto_enhance: true
-      backup_originals: true
     # Example additional site configuration:
     # - site_id: "mysite"
     #   path: "/var/www/mysite"
     #   domain: "mysite.example.com"
     #   auto_enhance: true
-    #   backup_originals: true
+
 
 # CLI enhancement configuration
 cli:
-  site_id: "demo"       # Default site ID for CLI operations
+  site_id: "default"    # Default site ID for CLI operations
   output: "./dist"      # Default output directory for enhanced files
   inject_demo_gate: true  # Inject demo gate in development mode if no gates exist