Add Sites Renderer service to Docker Compose and implement public endpoint for site definitions

- Introduced `igny8_sites` service in `docker-compose.app.yml` for serving deployed public sites.
- Updated `SitesRendererAdapter` to construct deployment URLs dynamically based on environment variables.
- Added `SiteDefinitionView` to provide a public API endpoint for retrieving deployed site definitions.
- Enhanced `loadSiteDefinition` function to prioritize API calls for site definitions over filesystem access.
- Updated frontend to utilize the new API endpoint for loading site definitions.

frontend/src/pages/Sites/Preview.tsx

@@ -53,18 +53,20 @@ export default function SitePreview() {
               // If deployment exists but no URL, construct from Sites Renderer
               // Sites Renderer should be accessible at a different port or subdomain
               // Check if we have the Sites Renderer URL configured
+              // Use VPS IP or configured URL for Sites Renderer
               const sitesRendererUrl = import.meta.env.VITE_SITES_RENDERER_URL || 
                                        (window as any).__SITES_RENDERER_URL__ || 
-                                       'http://localhost:8024';
+                                       'http://31.97.144.105:8024';
               setPreviewUrl(`${sitesRendererUrl}/${siteId}`);
             }
           } catch (error) {
             console.warn('No deployment record found:', error);
             // If blueprint is deployed but no deployment record, try Sites Renderer directly
             if (latestBlueprint.status === 'deployed') {
+              // Use VPS IP or configured URL for Sites Renderer
               const sitesRendererUrl = import.meta.env.VITE_SITES_RENDERER_URL || 
                                        (window as any).__SITES_RENDERER_URL__ || 
-                                       'http://localhost:8024';
+                                       'http://31.97.144.105:8024';
               setPreviewUrl(`${sitesRendererUrl}/${siteId}`);
             }
           }