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)

app/src/components/ServerTab/SettingRow.tsx

@@ -0,0 +1,62 @@
+import type { ReactNode } from 'react';
+
+/**
+ * A section header with title and optional description, separated by a border.
+ */
+export function SettingSection({
+  title,
+  description,
+  children,
+}: {
+  title?: string;
+  description?: string;
+  children: ReactNode;
+}) {
+  return (
+    <div className="space-y-1">
+      {title && <h3 className="text-sm font-medium">{title}</h3>}
+      {description && <p className="text-sm text-muted-foreground">{description}</p>}
+      <div className={`${title || description ? 'pt-3' : ''} space-y-0 divide-y divide-border/60`}>
+        {children}
+      </div>
+    </div>
+  );
+}
+
+/**
+ * A single settings row: label+description on the left, action on the right.
+ * Use for toggles, inputs, buttons, badges — any control type.
+ */
+export function SettingRow({
+  title,
+  description,
+  htmlFor,
+  action,
+  children,
+}: {
+  title: string;
+  description?: string;
+  htmlFor?: string;
+  /** Right-aligned control (checkbox, button, badge, etc.) */
+  action?: ReactNode;
+  /** Full-width content rendered below the label row (for sliders, inputs, etc.) */
+  children?: ReactNode;
+}) {
+  return (
+    <div className="py-3">
+      <div className="flex items-center justify-between gap-8">
+        <div className="min-w-0">
+          <label
+            htmlFor={htmlFor}
+            className="text-sm font-medium leading-none cursor-pointer select-none"
+          >
+            {title}
+          </label>
+          {description && <p className="text-sm text-muted-foreground mt-0.5">{description}</p>}
+        </div>
+        {action && <div className="shrink-0">{action}</div>}
+      </div>
+      {children && <div className="mt-3">{children}</div>}
+    </div>
+  );
+}