Add interactive layer management to Editor

- Click layer to toggle visibility and redraw canvas
- Click ▲/▼ buttons to reorder layers (z-index)
- Active layer highlighted with left red border
- Each layer now actually renders: bg/white, border/frame, pattern/suit symbol, text/corner labels
- Fix fabric.js imports (Canvas, FabricText, Rect)

frontend/node_modules/.vite/deps/_metadata.json

@@ -1,43 +1,43 @@
 {
-  "hash": "8c4b68ba",
-  "configHash": "34f6f529",
+  "hash": "76c4bd08",
+  "configHash": "3c200fce",
   "lockfileHash": "99e89a35",
-  "browserHash": "6a02d3bf",
+  "browserHash": "df8b7ff8",
   "optimized": {
     "axios": {
       "src": "../../axios/index.js",
       "file": "axios.js",
-      "fileHash": "9022993e",
+      "fileHash": "a369977c",
       "needsInterop": false
     },
     "element-plus": {
       "src": "../../element-plus/es/index.mjs",
       "file": "element-plus.js",
-      "fileHash": "ed152bc7",
+      "fileHash": "0a2f9603",
       "needsInterop": false
     },
     "fabric": {
       "src": "../../fabric/dist/index.min.mjs",
       "file": "fabric.js",
-      "fileHash": "14f1f947",
+      "fileHash": "a1369625",
       "needsInterop": false
     },
     "pinia": {
       "src": "../../pinia/dist/pinia.mjs",
       "file": "pinia.js",
-      "fileHash": "ecda6472",
+      "fileHash": "20bc890b",
       "needsInterop": false
     },
     "vue-router": {
       "src": "../../vue-router/dist/vue-router.mjs",
       "file": "vue-router.js",
-      "fileHash": "4a9d54f8",
+      "fileHash": "017f450e",
       "needsInterop": false
     },
     "vue": {
       "src": "../../vue/dist/vue.runtime.esm-bundler.js",
       "file": "vue.js",
-      "fileHash": "4a46bbb6",
+      "fileHash": "70ae02ae",
       "needsInterop": false
     }
   },