overhaul settings: split into routed sub-tabs, add server logs, changelog, reusable setting components

- Rename Server tab to Settings with horizontal sub-tab navigation (General, Generation, GPU, Logs, Changelog)
- All sub-tabs are proper routes under /settings/* with /server redirect for backwards compat
- General: connection settings, link cards (docs + discord), API reference card, app updates
- Generation: auto-chunking, crossfade, normalize, autoplay as SettingRow components
- GPU: info card with platform-aware icons (Apple logo for MPS), CUDA management, explainer text
- Logs: real-time server log viewer piped from Tauri sidecar via event system (Tauri-only)
- Changelog: parsed from CHANGELOG.md at build time via Vite virtual module plugin
- New reusable SettingRow/SettingSection components for consistent settings layout
- New Toggle (switch) UI component replacing checkboxes in settings
- Toast viewport now offsets when audio player is open
- Sidebar stays active on settings sub-routes (fuzzy matching)

tauri/src/platform/lifecycle.ts

@@ -1,6 +1,6 @@
 import { invoke } from '@tauri-apps/api/core';
 import { emit, listen } from '@tauri-apps/api/event';
-import type { PlatformLifecycle } from '@/platform/types';
+import type { PlatformLifecycle, ServerLogEntry } from '@/platform/types';
 
 class TauriLifecycle implements PlatformLifecycle {
   onServerReady?: () => void;
@@ -86,6 +86,20 @@ class TauriLifecycle implements PlatformLifecycle {
       console.error('Failed to setup window close handler:', error);
     }
   }
+
+  subscribeToServerLogs(callback: (entry: ServerLogEntry) => void): () => void {
+    let unlisten: (() => void) | null = null;
+
+    listen<ServerLogEntry>('server-log', (event) => {
+      callback(event.payload);
+    }).then((fn) => {
+      unlisten = fn;
+    });
+
+    return () => {
+      unlisten?.();
+    };
+  }
 }
 
 export const tauriLifecycle = new TauriLifecycle();