Webapp: Updates pages, image page tabs with review-before-save, BPRT sync

Updates group:
- Dell drivers and BIOS: check Dell's catalogs against all three driver maps
  and models.txt, download with a shared speed cap, repack, preview, apply
  with backups and rollback.
- iPXE boot files: check GitHub for the signed Secure Boot set, verify the
  sha256 and each file's signer, install atomically, roll back. Includes the
  by-hand procedure.
- Blancco: upload a release, stage it, test-boot it from the menu, activate,
  roll back.
- BPRT sync: validate a batch uploaded from the MediaCreator Lite cache
  (scripts/windows/Sync-BPRT.ps1 or a zip), show the diff, swap with the site
  overlay files kept.

Images: one sidebar entry per image with Overview, Drivers, Unattend and OS and
Packages tabs. Every save shows a diff first, keeps the file's format, makes a
backup and can be undone. Driver lint runs inline.

Enrollment: upload standard/engineer MCL packages, one per tenant/purpose,
with archive and restore. Hardware coverage counts engineer as Win11.

webapp/services/hardware_coverage.py

@@ -33,10 +33,12 @@ from pathlib import PurePosixPath
 import config
 
 # Images whose HardwareDriver.json is checked, with the Windows they deploy.
+# All three deploy Windows 11 now (engineer moved off Win10), so every one
+# counts toward a model's gaps.
 IMAGES = (
     ("gea-standard", "Win11"),
     ("gea-shopfloor", "Win11 LTSC"),
-    ("gea-engineer", "Win10"),
+    ("gea-engineer", "Win11"),
 )
 KEEP = 10  # serials / versions remembered per model
 
@@ -239,7 +241,7 @@ def coverage(include_ok=True):
         drivers = driver_status(model)
         bios = bios_status(model, rec.get("last_bios_version", ""))
         missing = [img for img, d in drivers.items()
-                   if d["status"] in ("no-entry", "zip-missing") and img != "gea-engineer"]
+                   if d["status"] in ("no-entry", "zip-missing")]
         gap = bool(missing) or bios["status"] in ("none", "file-missing")
         row = dict(rec, model=model, drivers=drivers, bios=bios, missing=missing,
                    gap=gap, dismissed=model in state["dismissed"])