fix(icon): wedding rings, and delete the skeleton favicon behind them

The event is a wedding, so the camera icon becomes two interlocking bands. Drawn rather
than sourced: at 16px in a tab anything finer than the stroke turns to smudge, which is
why the camera it replaces was three shapes and no more. White on #8a6a2b, the event's
own theme_primary, so the icon, the site and the PWA chrome finally agree -- the
manifest's theme_color was still the #2563eb from the camera branding.

The rings span x 88-424 and y 139-373 including stroke, inside the centre-80% safe zone,
so an Android circle crop cannot clip them.

Also removes a second, competing icon declaration. `+layout.svelte` imported
`$lib/assets/favicon.svg` -- the orange Svelte logo from the project skeleton, which Vite
inlined as a data URI into the layout bundle -- and applied it via `<svelte:head>`. Which
of the two won was left to the browser: the link in app.html is parsed from the initial
HTML, this one is added at hydration, and Chrome keeps the former. So the skeleton logo
did not usually show, but nothing guaranteed that, and `ssr = false` means the branded
link is the only one present at first paint anyway. app.html is now the single source and
the skeleton asset is gone.

frontend/static/icon.svg

@@ -1,12 +1,19 @@
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" width="512" height="512" role="img" aria-label="EventSnap">
-  <!-- Full-bleed brand background keeps the icon "maskable": safe content sits within the centre 80%. -->
-  <rect width="512" height="512" fill="#2563eb"/>
-  <g fill="none" stroke="#ffffff" stroke-width="22" stroke-linejoin="round" stroke-linecap="round">
-    <!-- Camera body -->
-    <rect x="116" y="172" width="280" height="200" rx="34"/>
-    <!-- Viewfinder bump -->
-    <path d="M212 172l24-34h40l24 34" fill="#ffffff" stroke="none"/>
-    <!-- Lens -->
-    <circle cx="256" cy="276" r="58"/>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" width="512" height="512" role="img" aria-label="Hochzeit von Julia &amp; Jonas">
+  <!-- Full-bleed brand background keeps the icon "maskable": safe content sits within the centre 80%
+       (51.2-460.8). The rings span x 88-424 and y 139-373 including stroke, so an Android circle
+       crop cannot clip them. -->
+  <rect width="512" height="512" fill="#8a6a2b"/>
+  <!-- Two interlocking bands. Deliberately just the two rings: no gem, no shine, no inner bevel.
+       This renders at 16px in a browser tab, where any detail smaller than the stroke width turns
+       into a smudge — the same reason the camera icon this replaces was three shapes and no more. -->
+  <g fill="none" stroke="#ffffff" stroke-width="26">
+    <circle cx="205" cy="256" r="104"/>
+    <circle cx="307" cy="256" r="104"/>
+    <!-- The interlock. Both circles above are drawn whole, so the right band covers the left one at
+         BOTH crossings and they read as merely overlapping. Redrawing this arc of the left band —
+         the segment through the upper intersection at (256, 165.4) — puts it back on top there
+         while the right stays on top at the lower crossing, which is what makes them look linked
+         rather than stacked. Keep it in sync if either circle moves. -->
+    <path d="M214.1 152.4A104 104 0 0 1 290.2 196.3"/>
   </g>
 </svg>

frontend/static/manifest.webmanifest

@@ -8,7 +8,7 @@
 	"display": "standalone",
 	"orientation": "portrait",
 	"background_color": "#ffffff",
-	"theme_color": "#2563eb",
+	"theme_color": "#8a6a2b",
 	"icons": [
 		{
 			"src": "/icon.svg",