Localization: removing a locale from "Available Locales" is silently reverted whenever its asset is reimported, including on a fresh checkout - so the active locale set differs between machines

Steps to reproduce:

1. Create a new project
2. Install the Localization package (com.unity.localization)
3. Open Edit > Project Settings > Localization and click "Create" to make the settings asset
4. Click "Add Locale", add three locales, and save them into a project folder. All three appear under "Available Locales"
5. Select one row in "Available Locales" and click "−". The list drops to two entries; the Locale asset remains in the Project window
6. Select that same Locale asset in the Project window
7. In the Inspector window for a selected locale, update the "Sort Order" number field, the name field, or the Addressable toggle - whichever your build shows
8. Press ⌘S
9. Return to Edit > Project Settings > Localization and look at "Available Locales"

Actual results: The removed locale is back in "Available Locales". Any reimport of the Locale asset re-registers it, so the removal survives only until the next import of that file. The removal is not persisted anywhere, and there is no way to keep a Locale asset in the project while leaving it out of the active settings

Expected results: The removal persists. Either the "−" button also removes the asset, or the removal is recorded so that reimporting the asset does not re-register it

Reproducible with versions: 1.5.12 (6000.5.7f1, 6000.6.0f1, 6000.7.0a6)

Tested on (OS): MacBook Pro - Tahoe 26.6.2

Notes:

Additional reproduction routes - any one of these also brings the locale back:

• Right-click the Locale asset > "Reimport"
• Right-click the containing folder > "Reimport"
• Delete the Library folder and reopen the project - which is also what a teammate gets on a fresh checkout
• Assets > "Reimport All"
• Any external tool or version-control operation that rewrites the .asset file

The revert is silent. No dialog, no Console message, no indication in the list that an entry was re-added. The user has no reason to re-check a list they already edited.