Fix bugs, convert thumbnail to png, add context menu

frontend/package-lock.json

@@ -1,14 +1,15 @@
 {
-  "name": "frontend",
-  "version": "0.0.0",
+  "name": "paperjet",
+  "version": "0.1.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
-      "name": "frontend",
-      "version": "0.0.0",
+      "name": "paperjet",
+      "version": "0.1.0",
       "dependencies": {
         "@tailwindcss/vite": "^4.3.0",
+        "date-fns": "^4.4.0",
         "fabric": "^7.4.0",
         "pdfjs-dist": "^6.0.227",
         "react": "^19.2.6",
@@ -22,7 +23,7 @@
         "@testing-library/jest-dom": "^6.9.1",
         "@testing-library/react": "^16.3.2",
         "@types/fabric": "^5.3.11",
-        "@types/node": "^24.12.3",
+        "@types/node": "^24.13.2",
         "@types/react": "^19.2.14",
         "@types/react-dom": "^19.2.3",
         "@vitejs/plugin-react": "^6.0.1",
@@ -2598,6 +2599,16 @@
         "node": "^20.19.0 || ^22.12.0 || >=24.0.0"
       }
     },
+    "node_modules/date-fns": {
+      "version": "4.4.0",
+      "resolved": "https://registry.npmjs.org/date-fns/-/date-fns-4.4.0.tgz",
+      "integrity": "sha512-+1UMbeh68lH1SegH83CGWwpb6OHHbpSgr3+s5Eww5M4CAgswBpoWS0AjTOfEJ33HiYKz1hdj/KTFprzXHmq/6w==",
+      "license": "MIT",
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/kossnocorp"
+      }
+    },
     "node_modules/debug": {
       "version": "4.4.3",
       "resolved": "https://registry.npmjs.org/debug/-/debug-4.4.3.tgz",
@@ -3508,7 +3519,6 @@
       "integrity": "sha512-ECi4Fi2f7BdJtUKTflYRTiaMxIB0O6zfR1fX0GXpUrf6flp8QIYn1UT20YQqdSOfk2dfkCwS8LAFoJDEppNK5Q==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "@asamuzakjp/css-color": "^5.1.11",
         "@asamuzakjp/dom-selector": "^7.1.1",