appview/pages: add favicon

based on lowercase IBM Plex Mono `t`, italic variant.

thanks to @t1c.dev!

Signed-off-by: oppiliappan <[e-mail]>

appview/pages/pages.go

···
 	return p.executeOrReload(name, w, "layouts/repobase", params)
 }
 
+func (p *Pages) Favicon(w io.Writer) error {
+	return p.executePlain("favicon", w, nil)
+}
+
 type LoginParams struct {
 	ReturnUrl string
 }

appview/pages/templates/favicon.html

···
+{{ define "favicon" }}
+<svg xmlns="http://www.w3.org/2000/svg" width="32" height="32">
+  <style>
+    .favicon-text {
+      fill: #000000;
+      stroke: none;
+    }
+
+    @media (prefers-color-scheme: dark) {
+      .favicon-text {
+        fill: #ffffff;
+        stroke: none;
+      }
+    }
+  </style>
+
+  <g style="display:inline">
+    <path d="M0-2.117h62.177v25.135H0z" style="display:inline;fill:none;fill-opacity:1;stroke-width:.396875" transform="translate(11.01 6.9)"/>
+    <path d="M3.64 22.787c-1.697 0-2.943-.45-3.74-1.35-.77-.9-1.156-2.094-1.156-3.585 0-.36.013-.72.038-1.08.052-.385.129-.873.232-1.464L.44 6.826h-5.089l.733-4.394h3.2c.822 0 1.439-.168 1.85-.502.437-.334.72-.938.848-1.812l.771-4.703h5.243L6.84 2.432h7.787l-.733 4.394H6.107L4.257 17.93l.77.27 6.015-4.742 2.775 3.161-2.313 2.005c-.822.694-1.568 1.31-2.236 1.85-.668.515-1.31.952-1.927 1.311a7.406 7.406 0 0 1-1.774.733c-.59.18-1.233.27-1.927.27z" 
+      aria-label="tangled.sh"
+      class="favicon-text"
+      style="font-size:16.2278px;font-family:'IBM Plex Mono';-inkscape-font-specification:'IBM Plex Mono, Normal';display:inline;fill-opacity:1"
+      transform="translate(11.01 6.9)"/>
+  </g>
+</svg>
+{{ end }}

appview/pages/templates/layouts/topbar.html

···
     <nav class="space-x-4 px-6 py-2 rounded bg-white dark:bg-gray-800 dark:text-white drop-shadow-sm">
         <div class="flex justify-between p-0 items-center">
             <div id="left-items">
-                <a href="/" hx-boost="true" class="flex gap-2 font-semibold italic">
+                <a href="/" hx-boost="true" class="flex gap-2 font-bold italic">
                   tangled<sub>alpha</sub>
                 </a>
             </div>

appview/state/router.go

···
 		s.pages,
 	)
 
+	router.Get("/favicon.svg", s.Favicon)
+	router.Get("/favicon.ico", s.Favicon)
+
 	router.HandleFunc("/*", func(w http.ResponseWriter, r *http.Request) {
 		pat := chi.URLParam(r, "*")
 		if strings.HasPrefix(pat, "did:") || strings.HasPrefix(pat, "@") {

appview/state/state.go

···
 	return state, nil
 }
 
+func (s *State) Favicon(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "image/svg+xml")
+	w.Header().Set("Cache-Control", "public, max-age=31536000") // one year
+	w.Header().Set("ETag", `"favicon-svg-v1"`)
+
+	if match := r.Header.Get("If-None-Match"); match == `"favicon-svg-v1"` {
+		w.WriteHeader(http.StatusNotModified)
+		return
+	}
+
+	s.pages.Favicon(w)
+}
+
 func (s *State) TermsOfService(w http.ResponseWriter, r *http.Request) {
 	user := s.oauth.GetUser(r)
 	s.pages.TermsOfService(w, pages.TermsOfServiceParams{