#1361 Feature Request: Support recording with screen turned off (for timelapses) and Floating Window (PiP) mode

[alexa]

I would like to request two interrelated features that would drastically improve Open Camera’s usability for long-term recordings and multitasking:

1. Support for Recording with the Screen Turned Off (Crucial for Timelapses)
   Currently, when taking multi-hour interval photo sequences or long videos for timelapses, keeping the smartphone screen fully active causes severe battery drain and excessive device heating. It would be highly beneficial to add a background service or a deep-dimmed black overlay mode that allows the camera sensor to continue capturing frames while the physical screen is completely turned off or blacked out, similar to background video recorder (BVR) applications.

2. Floating Window / Picture-in-Picture (PiP) Mode
   It would be amazing to have a toggle to minimize the active camera preview into a small, movable floating window. This would allow users to monitor the camera angle, focus, or recording status while using other apps on the smartphone (e.g., managing navigation, checking notes, or monitoring system resources).

Both of these features would make Open Camera the ultimate tool for advanced mobile time-lapse photographers and power users. Thank you for your incredible work on this project!