Config for change Video Transcoding coder

[lyj0309]

Describe the problem this solves and why this would be valuable to many users:

PhotoPrism only supports the H.264 video codec, which limits users who want to upload and manage videos encoded with more modern standards such as H.265/HEVC. The H.265 codec offers significantly reduced file sizes at the same quality level compared to H.264, which is especially beneficial for users looking to optimize storage use and handle high-resolution video content. Supporting a broader range of video codecs would make PhotoPrism more flexible and useful for a wider audience, enhancing its appeal as a comprehensive photo and video management tool.

Describe the solution you'd like:
I propose adding a configuration option in PhotoPrism that allows users to select their preferred video encoding format. This feature could be implemented in the settings menu, where users can choose from supported codecs like H.264, H.265, and possibly others in the future. This would provide greater control over media management and help optimize storage, especially for users dealing with large video libraries.

Describe alternatives you've considered:
Use a lower bit rate, but with worse picture quality.

Additional context:
https://caniuse.com/?search=hevc

[lastzero]

Note that while Chrome generally supports HEVC, this depends on the runtime environment. On Linux, for example, it doesn't work when I use the Nvidia drivers that come with Ubuntu / Mint. So it's not suitable as default codec for all browsers / users yet. I also expect HEVC to be more computationally expensive than AVC, so transcoding would likely require hardware encoding support on your server or NAS device.