add model/design

pubspec.lock

@@ -377,6 +377,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "7.0.1"
+  file_picker:
+    dependency: "direct main"
+    description:
+      name: file_picker
+      sha256: "825aec673606875c33cd8d3c4083f1a3c3999015a84178b317b7ef396b7384f3"
+      url: "https://pub.dev"
+    source: hosted
+    version: "8.0.7"
   file_selector_linux:
     dependency: transitive
     description:
@@ -1353,6 +1361,30 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.4.0"
+  url_launcher:
+    dependency: "direct main"
+    description:
+      name: url_launcher
+      sha256: f6a7e5c4835bb4e3026a04793a4199ca2d14c739ec378fdfe23fc8075d0439f8
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.2"
+  url_launcher_android:
+    dependency: transitive
+    description:
+      name: url_launcher_android
+      sha256: "5c8b6c2d89a78f5a1cca70a73d9d5f86c701b36b42f9c9dac7bad592113c28e9"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.24"
+  url_launcher_ios:
+    dependency: transitive
+    description:
+      name: url_launcher_ios
+      sha256: "6b63f1441e4f653ae799166a72b50b1767321ecc263a57aadf825a7a2a5477d9"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.5"
   url_launcher_linux:
     dependency: transitive
     description:
@@ -1361,6 +1393,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.2.1"
+  url_launcher_macos:
+    dependency: transitive
+    description:
+      name: url_launcher_macos
+      sha256: "8262208506252a3ed4ff5c0dc1e973d2c0e0ef337d0a074d35634da5d44397c9"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.4"
   url_launcher_platform_interface:
     dependency: transitive
     description: