rename(547): the mark is a clasped grimoire

favicon.svg is a violet book with gold corners and clasp and a four-pointed star
in a ring, replacing the indigo book with a spark. It is rendered to 192 and 512
PNG app icons and a 180 touch icon on the page surface.

manifest.json lists those icons instead of a favicon.ico that never existed. It
describes the product as the README does, and takes its colours from the design
system's page surface. index.html's theme-color follows.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/public/manifest.json

@@ -1,17 +1,27 @@
 {
   "name": "Fabled Grimoire",
   "short_name": "Grimoire",
-  "description": "Your self-hosted second brain with AI assistance",
+  "description": "A self-hosted work system-of-record for software projects, built to be driven by Claude Code.",
   "start_url": "/",
   "display": "standalone",
-  "background_color": "#1a1a2e",
-  "theme_color": "#6c63ff",
+  "background_color": "#14171A",
+  "theme_color": "#14171A",
   "orientation": "portrait-primary",
   "icons": [
     {
-      "src": "/favicon.ico",
+      "src": "/favicon.svg",
       "sizes": "any",
-      "type": "image/x-icon"
+      "type": "image/svg+xml"
+    },
+    {
+      "src": "/icon-192.png",
+      "sizes": "192x192",
+      "type": "image/png"
+    },
+    {
+      "src": "/icon-512.png",
+      "sizes": "512x512",
+      "type": "image/png"
     }
   ]
 }