feat: Add multi-canvas system with project canvas support

- Add project_canvas and canvas_components tables for persistent canvas storage
- Add ProjectCanvas store with full CRUD operations
- Add ProjectCanvasPage for rendering saved canvas with components
- Add ProjectsPage for managing canvas list (create, clone, delete)
- Add HomePage that loads default canvas or falls back to dynamic canvas
- Add toolbar support for displaying canvas as pages with custom icons
- Add component usage validation to prevent deletion of components in use
- Add MCP tools for canvas management (list, create, update, delete, clone)
- Update router with /canvas/:id and /projects routes
- Update Toolbar to show dynamic canvas pages from database

frontend/src/App.vue

@@ -10,6 +10,8 @@ import { initToolRegistry, activatePageTools, initToolsOnRefresh } from './servi
 const route = useRoute()
 const router = useRouter()
 
+type PageName = 'home' | 'canvas' | 'components' | 'themes' | 'projects' | 'project-canvas'
+
 onMounted(async () => {
   // Initialize WebMCP connection
   await initWebMCP()
@@ -19,13 +21,13 @@ onMounted(async () => {
 
   // Initialize tools for current page (handles refresh)
   const currentPage = (route.name as string) || 'canvas'
-  initToolsOnRefresh(currentPage as 'canvas' | 'components' | 'themes')
+  initToolsOnRefresh(currentPage as PageName)
 })
 
 // Watch for route changes and update tools
 watch(() => route.name, (newPage) => {
   if (newPage) {
-    activatePageTools(newPage as 'canvas' | 'components' | 'themes')
+    activatePageTools(newPage as PageName)
   }
 })
 </script>