perf: reduce portable build size ~40MB — replace winsdk/wmi, migrate cv2 to Pillow

- Replace winsdk (~35MB) with winrt packages (~2.5MB) for OS notification
  listener. API is identical, 93% size reduction.
- Replace wmi (~3-5MB) with ctypes for monitor names (EnumDisplayDevicesW)
  and camera names (SetupAPI). Zero external dependency.
- Migrate cv2.resize/imencode/LUT to Pillow/numpy in 5 files (filters,
  preview helpers, kc_target_processor). OpenCV only needed for camera
  and video stream now.
- Fix DefWindowProcW ctypes overflow on 64-bit Python (pre-existing bug
  in platform_detector display power listener).
- Fix openLightbox import in streams-capture-templates.ts (was using
  broken window cast instead of direct import).
- Add mandatory data migration policy to CLAUDE.md after silent data
  loss incident from storage file rename without migration.

server/src/wled_controller/static/js/features/streams-capture-templates.ts

@@ -15,7 +15,7 @@ import {
 import { API_BASE, getHeaders, fetchWithAuth, escapeHtml } from '../core/api.ts';
 import { t } from '../core/i18n.ts';
 import { Modal } from '../core/modal.ts';
-import { showToast, showConfirm, showOverlaySpinner, hideOverlaySpinner, updateOverlayPreview, setupBackdropClose } from '../core/ui.ts';
+import { showToast, showConfirm, openLightbox, showOverlaySpinner, hideOverlaySpinner, updateOverlayPreview, setupBackdropClose } from '../core/ui.ts';
 import { openDisplayPicker, formatDisplayLabel } from './displays.ts';
 import {
     getEngineIcon,
@@ -500,7 +500,7 @@ export function _runTestViaWS(wsPath: string, queryParams: any = {}, firstMessag
             } else if (msg.type === 'result') {
                 gotResult = true;
                 hideOverlaySpinner();
-                (window as any).openLightbox(msg.full_image, buildTestStatsHtml(msg));
+                openLightbox(msg.full_image, buildTestStatsHtml(msg));
                 ws.close();
             } else if (msg.type === 'error') {
                 hideOverlaySpinner();