Update requirement files with new feature templates and fix backend API error message, along with mobile project config updates and documentation improvements

03_source/mobile.trunk.1/public/manifest.json

@@ -0,0 +1,21 @@
+{
+  "short_name": "Ionic React Conf",
+  "name": "Ionic React Conf",
+  "icons": [
+    {
+      "src": "assets/icon/favicon.png",
+      "sizes": "64x64 32x32 24x24 16x16",
+      "type": "image/x-icon"
+    },
+    {
+      "src": "assets/icon/icon.png",
+      "type": "image/png",
+      "sizes": "512x512",
+      "purpose": "maskable"
+    }
+  ],
+  "start_url": ".",
+  "display": "standalone",
+  "theme_color": "#ffffff",
+  "background_color": "#ffffff"
+}