Immuch360 desktop build 21

Immuch360 desktop build 21, for Windows, Linux and macOS, a test build from the same code as Android build 41: Gaussian splats to walk through on the computer, splat scenes kept on your Immich server, AV2 videos (experimental), Make a splat scene (AI) on Windows (experimental), and 8K videos that no longer stutter on a Windows laptop with two graphics chips.

• Gaussian splats on the computer (experimental): a .spz or .ply of your library folders or of a share opens in a viewer window over the app, at a click, with "Open a splat file", with "Open with" from your file manager or by a drop on the window.
• Splat photos and Save to Immich: Immich does not take .spz and .ply files, so Save to Immich, in the viewer and for a splat selected in a share, turns a scene into a splat photo, a JPEG of the view you see with the whole scene inside the same file.
• Make a splat scene (AI), on Windows (experimental): select 20 photos or more of a place or an object (200 at most are used, spread in time), or one video of 10 seconds to 5 minutes, then Make a splat scene (AI): COLMAP 4.2.1, our build without its GPL parts, places the photos in 3D on the processor, and Brush 0.3.0 trains the splat on the graphics card with Vulkan.
• AV2 videos (experimental): Immuch360 Desktop reads AV2 files (.ivf, .obu), with software decoding, as fast as your computer allows: from the folders of the library, from the shares you open in the app, and with Open with from your file manager.
• 8K videos on a Windows laptop with two graphics chips: the app asked for nothing, so Windows ran all of it on the integrated chip, where an 8K film stuttered and showed black frames.
• Video decoding, in the details of a video: under Video source, while a video plays, a line says how it is decoded and on which chip, for example "Hardware, on NVIDIA GeForce RTX 4060 Laptop GPU", "each frame copied to memory", "Software, on the processor", or for AV2 how many pictures a second this computer decodes against what the video needs.
• 360° panoramas on a graphics card of 8 GB: before a panorama, the app now frees the graphics memory it holds itself (paused videos and cached pictures), and when 5.1 to 6 GiB of the card are free it makes the panorama from a lighter reference (capped at 1280 x 640).
• The folder library at the start of a new profile: its index, opened from several places at once at the very start, no longer fails with "database is locked" (a file given to the program at that moment could fail to open).