Default/persistent ISO and shutter speed values for quick shots

[seniordevel]

Checklist

• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the request will be dismissed otherwise.
• This issue contains only one feature request.
• I have read and understood the contribution guidelines.

Feature description

It would be great to have a way to set default ISO and/or shutter speed values that the app applies automatically and remembers between sessions, so the correction only needs to be dialed in once and every quick shot afterward benefits from it.

Why do you want this feature?

Low-budget phones (e.g. Moto G15) often have camera hardware that struggles with exposure, and third-party camera apps tend to overexpose in tricky lighting. Motorola's own camera app handles this correctly, so it's clearly fixable in software.

Additional information

This is related to #284 (manual exposure controls), but a distinct request.

Manual ISO/shutter speed controls (as requested in #284) would help, but aren't enough on their own: I often need to take a photo quickly, with no time to open an exposure menu and adjust sliders first.