Show removed metadata in strip UI after download

Extracts EXIF, ICC, IPTC, XMP metadata before stripping and displays
it in a card below the drop zone — camera make/model, GPS, date taken,
lens, exposure settings, etc. GPS location gets a warning highlight.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

package.json

@@ -9,6 +9,7 @@
   },
   "dependencies": {
     "archiver": "^6.0.2",
+    "exif-reader": "^2.0.3",
     "express": "^4.19.2",
     "libheif-js": "^1.18.0",
     "sharp": "^0.33.5"