feat(bd-2vw): display raw lore data in debug view

Add DebugView component to show raw lore status data for visual
verification that the data pipeline works end-to-end:
- Frontend -> Tauri IPC -> Rust backend -> lore CLI -> parsed data

New files:
- src/components/DebugView.tsx - Debug component with health indicator
- src/hooks/useLoreData.ts - TanStack Query hook for lore status
- tests/components/DebugView.test.tsx - Component tests
- tests/hooks/useLoreData.test.ts - Hook tests

Modified:
- src/App.tsx - Add QueryClientProvider wrapper
- src/stores/nav-store.ts - Add 'debug' ViewId
- src/components/AppShell.tsx - Add Debug nav tab and view routing
- tests/components/AppShell.test.tsx - Update tests for new nav

src/stores/nav-store.ts

@@ -9,7 +9,7 @@ import { create } from "zustand";
 import { persist, createJSONStorage } from "zustand/middleware";
 import { getStorage } from "@/lib/tauri-storage";
 
-export type ViewId = "focus" | "queue" | "inbox";
+export type ViewId = "focus" | "queue" | "inbox" | "settings" | "debug";
 
 export interface NavState {
   activeView: ViewId;