Windows compatible filenames: auto rename

[tobiasKaminsky]

⚠️ Only auto rename when capability is set ⚠️

On mobile:

• rename before upload (from external apps, e.g. mail attachement directly saved to app)

On desktop:

• rename before create/edit

Both should follow approach by onedrive:
https://stadt-bremerhaven.de/microsoft-onedrive-leerzeichen-am-ende-von-datei-und-ordnernamen-werden-automatisch-entfernt/

• Android: Feature - Auto Rename android#13583
• iOS: Windows compatible filenames: auto rename ios#3091
• Desktop: Auto rename files with invalid characters desktop#5809

[tobiasKaminsky]

Approach by onedrive:

• auto rename only
  • name with trailing/leading whitespace
  • name ending with a "."
  • names with not-allowed unicode char (https://docs.microsoft.com/windows/desktop/intl/unicode)
  • names with https://docs.microsoft.com/windows/desktop/intl/surrogates-and-supplementary-characters
• replace every non-valid character with a "_"
  • e.g. ".file" -> "_file"

--> for all other offer rename option (if possible)

[alperozturk96]

@tobiasKaminsky @susnux

Don't we need new OC capability for following ones:

names with not-allowed unicode char (https://docs.microsoft.com/windows/desktop/intl/unicode)
names with https://docs.microsoft.com/windows/desktop/intl/surrogates-and-supplementary-characters

Or it will be included in the currently existed ones?