Screen curtain: add option to speak/display toggle messages #19441

Is your feature request related to a problem? Please describe

Currently, NVDA has an option to "Play sound when toggling Screen Curtain". When this is enabled, sounds are played when Screen Curtain is turned on or off. Importantly, these sounds are played regardless of whether Screen Curtain is turned on or off as a result of a gesture or because it is enabled in NVDA's config. The result is that Screen Curtain provides the following types of feedback:

Thus, users who are willing and able to perceive and understand an earcon are always able to configure NVDA to indicate when Screen Curtain is turned on or off, regardless of the trigger. Braille-only users, or users who are unable to perceive or understand an earcon are not alerted when Screen Curtain is turned on or off.

Describe the solution you'd like

Add an option to emit speech and/or braille alerts when Screen Curtain is turned on or off, regardless of the trigger. This could look like:

• Updating the current option to send a braille message when Screen Curtain is toggled if a sound is played; or
• Changing the current setting to allow the user to choose any combination of speech, braille and sound when Screen Curtain is toggled (a la spelling error reporting).

Describe alternatives you've considered

Remove the option to play a sound and either:

• Always send a ui.message when Screen Curtain is turned on or off; or
• Only send a ui.message when Screen Curtain is toggled with a gesture. This brings it in to line with other settings, which aren't announced simply because they're enabled in the config; or
• Allow the user to choose among these options.

Additional context