feat: refactor monolithic App.vue into modular Vue component architecture

- Extract 711-line App.vue into 15+ focused files across 5 directories
- Add data layer (icons, metrics, policies, auditTrail, requests)
- Add composables (useNavigation, useRequests, useChat, useToast)
- Add layout components (SidebarRail, TopBar, FilterBar)
- Add shared components (PanelHead, InfoRow, ToastNotification)
- Add business component (RequestTable) and 5 view components
- Extract global CSS to assets/styles/global.css
- Add start.sh with WSL/Windows cross-platform support
- Add .gitignore for node_modules, dist, and IDE dirs

src/data/icons.js

@@ -0,0 +1,11 @@
+const iconPath = (content) => `<svg viewBox="0 0 24 24" aria-hidden="true">${content}</svg>`
+
+export const icons = {
+  dashboard: iconPath('<path d="M3 13h8V3H3z"/><path d="M13 21h8V11h-8z"/><path d="M13 3h8v6h-8z"/><path d="M3 21h8v-6H3z"/>'),
+  list: iconPath('<path d="M8 6h13"/><path d="M8 12h13"/><path d="M8 18h13"/><path d="M3 6h.01"/><path d="M3 12h.01"/><path d="M3 18h.01"/>'),
+  file: iconPath('<path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"/><path d="M14 2v6h6"/><path d="M8 13h8"/><path d="M8 17h5"/>'),
+  audit: iconPath('<path d="M12 8v4l3 3"/><path d="M3.05 11a9 9 0 1 1 .5 4"/><path d="M3 4v7h7"/>'),
+  search: iconPath('<circle cx="11" cy="11" r="8"/><path d="m21 21-4.3-4.3"/>'),
+  check: iconPath('<path d="M20 6 9 17l-5-5"/>'),
+  message: iconPath('<path d="M21 15a4 4 0 0 1-4 4H7l-4 4V7a4 4 0 0 1 4-4h10a4 4 0 0 1 4 4z"/>')
+}