appview: follow web app manifest standard

- `id` member in webmanifest should be url format based on spec.
- it is recommended to use `application/mniafest+json` mimetype
- changing the name from `pwa-manifest.json` to `manifest.webmanifest`

Reference: <https://www.w3.org/TR/appmanifest/>

Signed-off-by: Seongmin Lee <[e-mail]>

appview/pages/templates/layouts/base.html

···
             <link rel="preconnect" href="https://avatar.tangled.sh" />
             <link rel="preconnect" href="https://camo.tangled.sh" />
 
-            <!-- pwa manifest -->
-            <link rel="manifest" href="/pwa-manifest.json" />
+            <!-- web app manifest -->
+            <link rel="manifest" href="/manifest.webmanifest" />
 
             <!-- preload main font -->
             <link rel="preload" href="/static/fonts/InterVariable.woff2" as="font" type="font/woff2" crossorigin />

appview/pages/templates/user/completeSignup.html

···
                 content="complete your signup for tangled"
             />
             <script src="/static/htmx.min.js"></script>
-            <link rel="manifest" href="/pwa-manifest.json" />
+            <link rel="manifest" href="/manifest.webmanifest" />
             <link
                 rel="stylesheet"
                 href="/static/tw.css?{{ cssContentHash }}"

appview/pages/templates/user/login.html

···
             <meta property="og:url" content="https://tangled.org/login" />
             <meta property="og:description" content="login to for tangled" />
             <script src="/static/htmx.min.js"></script>
-            <link rel="manifest" href="/pwa-manifest.json" />
+            <link rel="manifest" href="/manifest.webmanifest" />
             <link rel="stylesheet" href="/static/tw.css?{{ cssContentHash }}" type="text/css" />
             <title>login &middot; tangled</title>
         </head>

appview/pages/templates/user/signup.html

···
             <meta property="og:url" content="https://tangled.org/signup" />
             <meta property="og:description" content="sign up for tangled" />
             <script src="/static/htmx.min.js"></script>
-            <link rel="manifest" href="/pwa-manifest.json" />
+            <link rel="manifest" href="/manifest.webmanifest" />
             <link rel="stylesheet" href="/static/tw.css?{{ cssContentHash }}" type="text/css" />
             <title>sign up &middot; tangled</title>
 

appview/state/router.go

···
 
 	router.Get("/favicon.ico", s.pages.StaticRedirect("/static/favicon.ico"))
 	router.Get("/favicon.svg", s.pages.StaticRedirect("/static/favicon.svg"))
-	router.Get("/pwa-manifest.json", s.PWAManifest)
+	router.Get("/manifest.webmanifest", s.WebAppManifest)
 	router.Get("/robots.txt", s.RobotsTxt)
 
 	userRouter := s.UserRouter(&middleware)

appview/state/state.go

···
 }
 
 // https://developer.mozilla.org/en-US/docs/Web/Progressive_web_apps/Manifest
+// https://www.w3.org/TR/appmanifest/
 const manifestJson = `{
   "name": "tangled",
   "description": "tightly-knit social coding.",
···
     }
   ],
   "start_url": "/",
-  "id": "org.tangled",
+  "id": "https://tangled.org",
 
   "display": "standalone",
   "background_color": "#111827",
   "theme_color": "#111827"
 }`
 
-func (p *State) PWAManifest(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Content-Type", "application/json")
+func (p *State) WebAppManifest(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/manifest+json")
 	w.Write([]byte(manifestJson))
 }