feat(stats): add stats server, API endpoints, config, and Anki integration

- Hono HTTP server with 20+ REST endpoints for stats data
- Stats overlay BrowserWindow with toggle keybinding
- IPC channel definitions and preload bridge
- Stats config section (toggleKey, serverPort, autoStartServer, autoOpenBrowser)
- Config resolver for stats section
- AnkiConnect proxy endpoints (guiBrowse, notesInfo)
- Note ID passthrough in card mining callback chain
- Stats CLI command with autoOpenBrowser respect

src/core/services/startup-bootstrap.test.ts

@@ -34,6 +34,7 @@ function makeArgs(overrides: Partial<CliArgs> = {}): CliArgs {
     anilistSetup: false,
     anilistRetryQueue: false,
     dictionary: false,
+    stats: false,
     jellyfin: false,
     jellyfinLogin: false,
     jellyfinLogout: false,