Refactor Site Builder Integration and Update Component Structure

- Removed the separate `igny8_sites` service from Docker Compose, integrating its functionality into the main app.
- Updated the Site Builder components to enhance user experience, including improved loading states and error handling.
- Refactored routing and navigation in the Site Builder Wizard and Preview components for better clarity and usability.
- Adjusted test files to reflect changes in import paths and ensure compatibility with the new structure.

frontend/src/pages/Sites/Builder/Wizard.tsx

@@ -214,15 +214,30 @@ export default function SiteBuilderWizard() {
                   <span>Pages generated</span>
                   <span>{pages.length}</span>
                 </div>
-                <Button
-                  variant="outline"
-                  tone="brand"
-                  fullWidth
-                  startIcon={<RefreshCw size={16} />}
-                  onClick={() => refreshPages(activeBlueprint.id)}
-                >
-                  Sync pages
-                </Button>
+                <div className="flex flex-col gap-3 sm:flex-row">
+                  <Button
+                    variant="outline"
+                    tone="brand"
+                    fullWidth
+                    startIcon={<RefreshCw size={16} />}
+                    onClick={() => refreshPages(activeBlueprint.id)}
+                  >
+                    Sync pages
+                  </Button>
+                  <Button
+                    variant="soft"
+                    tone="brand"
+                    fullWidth
+                    disabled={isGenerating}
+                    onClick={() =>
+                      loadBlueprint(activeBlueprint.id).then(() =>
+                        navigate("/sites/builder/preview"),
+                      )
+                    }
+                  >
+                    Open preview
+                  </Button>
+                </div>
               </div>
             ) : (
               <div className="mt-4 rounded-2xl border border-dashed border-gray-200 bg-gray-50/60 p-6 text-center text-sm text-gray-500 dark:border-white/10 dark:bg-white/[0.03] dark:text-white/60">