Fix safari maskable (#1004)

* fix maskable

* update manifest

Author: maxence-charriere

pkg/app/gen/manifest.webmanifest

@@ -3,26 +3,26 @@
   "name": "{{.Name}}",
   "description": "{{.Description}}",
   "icons": [
-    {
+    {{if .MaskableIcon}}{
+      "src": "{{.MaskableIcon}}",
+      "type": "image/png",
+      "purpose": "maskable",
+      "sizes": "512x512"
+    },{{end}}
+    {{if .SVGIcon}}{
       "src": "{{.SVGIcon}}",
       "type": "image/svg+xml",
       "sizes": "any"
-    },
-    {
+    },{{end}}
+    {{if .LargeIcon}}{
       "src": "{{.LargeIcon}}",
       "type": "image/png",
       "sizes": "512x512"
-    },
+    },{{end}}
     {
       "src": "{{.DefaultIcon}}",
       "type": "image/png",
       "sizes": "192x192"
-    },
-    {
-      "src": "{{.MaskableIcon}}",
-      "type": "image/png",
-      "purpose": "maskable",
-      "sizes": "192x192"
     }
   ],
   "scope": "{{.Scope}}",

pkg/app/http.go

@@ -794,7 +794,7 @@ type Icon struct {
 	SVG string
 
 	// Maskable specifies the path or URL to an adaptive icon designed for various
-	// operating system shapes. This icon must be a PNG image with 192x192 pixels.
+	// operating system shapes. This icon must be a PNG image with 512x512 pixels.
 	//
 	// Used in PWA manifests and as meta tags for Apple browsers, these icons adapt
 	// to device or browser shape requirements, avoiding unsightly cropping.