Initial commit: mumh5, a modern Mumble client

Electron desktop app with a Svelte 5 interface for any Mumble server.

- Mumble protocol core: TLS, handshake, channels, users, text, plugin data,
  client-side pacing of Murmur's rate limits
- Voice: WebCodecs Opus over the TCP tunnel, voice activity, push to talk,
  always-on, devices, per-user volume and local mute
- Several servers at once, voice on one; server rail with icons and ordering
- Chat: channels, direct messages, side chat, file sharing through f0ckm,
  inline images without it, click-to-play YouTube
- Profiles with rich descriptions, registration, rename, nicknames,
  connection information and moderation menus
- Identity wizard, multiple identities, PKCS#12 import/export, desktop
  Mumble certificate import, certificate pinning and viewer
- Tray icon with voice state
- Unit, server and end-to-end tests against a real Murmur

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

src/ui/Avatar.svelte

@@ -0,0 +1,19 @@
+<script lang="ts">
+  let { name, size = 32, speaking = false }: { name: string; size?: number; speaking?: boolean } = $props();
+
+  const hue = $derived([...name].reduce((h, c) => (h * 31 + c.charCodeAt(0)) >>> 0, 7) % 360);
+</script>
+
+<span class="avatar" class:speaking style:width="{size}px" style:height="{size}px"
+  style:font-size="{Math.round(size * 0.45)}px" style:background="hsl({hue} 45% 38%)">
+  {(name.trim()[0] ?? '?').toUpperCase()}
+</span>
+
+<style>
+  .avatar {
+    flex: none; display: inline-flex; align-items: center; justify-content: center;
+    font-weight: 700; color: #fff; user-select: none; box-shadow: 0 0 0 2px transparent;
+    transition: box-shadow 80ms;
+  }
+  .speaking { box-shadow: 0 0 0 2px var(--speaking); }
+</style>