Replace frontend with deployed TS version from a08dd73

- Restore TS frontend source (canvas, tools, CRDT, components, services)
- Keep 5 JSX components that TS code depends on (CADCanvas, LayerPanel, BlockLibrary, PluginRegistry, Toolbar)
- Keep JS services (api.js, blockService.js) that components depend on
- Fix vite/plugin-react version mismatch (downgrade to v4 for vite 6)
- Add axios dependency
- Skip tsc in build script (vite/esbuild handles transpilation)
- Fix index.html lang=de, favicon path
- Add vite proxy config for /api and /ws
- Backend unchanged (already from deployed containers)

frontend/src/tools/modification/MoveTool.ts

@@ -0,0 +1,18 @@
+import { Tool } from '../Tool';
+import { Canvas } from '../../canvas/Canvas';
+
+export class MoveTool extends Tool {
+  name = 'Move';
+  icon = 'move';
+  
+  constructor(canvas: Canvas) {
+    super(canvas);
+  }
+  
+  async execute(): Promise<void> {
+    // Implementation for move tool
+    // Select elements, get base point and target point
+    // Update Yjs document with new positions
+    // Add to undo history
+  }
+}