feat(clean): remove stale iOS/iPadOS .ipsw software updates

[sebastianbreguel]

Summary

Adds clean_cached_device_firmware() that removes cached .ipsw firmware installers from ~/Library/iTunes/{iPhone,iPad,iPod} Software Updates/ and Apple Configurator 2's nested cache under ~/Library/Group Containers/*.group.com.apple.configurator/.

.ipsw = full iOS/iPadOS firmware image (~5–8GB each) dropped by Finder/iTunes when you restore or update a device over cable, or by Apple Configurator 2 when managing device fleets. Once applied they're dead weight — Apple re-downloads on demand.

Who this actually helps

Honest scope: probably <10% of users have any .ipsw on disk (OTA updates from the device itself don't touch the Mac). But when the files are there, the win is huge:

• iOS developers restoring test devices
• Apple Configurator 2 users (fleet management — firmware accumulates fast)
• Anyone who restored an iPhone/iPad via cable and never looked at that folder again

For the other 90% it's a silent no-op (one find at maxdepth 1, negligible cost). Same profile as Xcode DeviceSupport cleanup (#519): nicho, pero cuando aplica se liberan decenas de GB.

Before / After

Before — firmware files sit unused, eating disk:

$ du -sh ~/Library/iTunes/iPhone\ Software\ Updates/
 12G    /Users/you/Library/iTunes/iPhone Software Updates/

$ ls ~/Library/iTunes/iPhone\ Software\ Updates/
iPhone15,2_17.5_21F79_Restore.ipsw     6.1G
iPhone17,1_18.0_22A3354_Restore.ipsw   5.9G

$ mo clean
...
  → Device backups
    ⚠ iOS backups: 3.2G, Path: ~/Library/Application Support/MobileSync/Backup
  (firmware left untouched — 12G wasted)

After — firmware removed, backups still respected:

$ mo clean --dry-run
...
  → Device backups & firmware
    ↪ Cached device firmware, 2 files, 12G dry
    ⚠ iOS backups: 3.2G, Path: ~/Library/Application Support/MobileSync/Backup

$ mo clean
...
  → Device backups & firmware
    ✓ Cached device firmware, 2 files, 12G
    ⚠ iOS backups: 3.2G, Path: ~/Library/Application Support/MobileSync/Backup

$ du -sh ~/Library/iTunes/iPhone\ Software\ Updates/
 0B     /Users/you/Library/iTunes/iPhone Software Updates/

User with no cached firmware (majority case):

$ mo clean
...
  → Device backups & firmware
    ⚠ iOS backups: 3.2G, Path: ~/Library/Application Support/MobileSync/Backup
  (no firmware line → function silently no-ops)

Design choices

• Never touches backups under MobileSync/ — only .ipsw files at the firmware paths
• Dry-run aware, whitelist-respecting, size reporting, counter integration — matches clean_chrome_old_versions pattern
• Registers whitelist sentinels in manage/whitelist.sh so users discover and protect the paths via mo clean --whitelist:

  [ ] iOS/iPadOS device firmware (.ipsw) from iTunes/Finder
  [ ] Apple Configurator 2 device firmware (.ipsw)
  

• Section renamed from Device backups to Device backups & firmware (firmware isn't a backup)

Test plan

• bats tests/clean_cached_device_firmware.bats — 6/6 pass

  • no-op when empty
  • dry-run reports iTunes dirs
  • finds nested .ipsw under Apple Configurator 2 Group Container
  • non-dry-run actually deletes
  • dry-run with real safe_remove (no mock) leaves filesystem untouched
  • respects whitelist

• Regression: bats tests/clean_browser_versions.bats tests/clean_user_core.bats all green

• Verified no-op path on a real Mac with zero .ipsw files (no false positives, no errors)

• Manual validation on real Mac: created 10MB fixture .ipsw, ran ./mo clean --dry-run, verified output:

  ➤ Device backups & firmware
    → Cached device firmware, 1 files, 10.5MB dry
  

  Fixture cleaned up after test.

[tw93]

@sebastianbreguel thanks for this. I kept the feature, pushed a small maintainer follow-up so the cleanup stats only count successful removals, and merged it now.