[RFC] warning when multiple FFMPEG detected
Add a warning message when multiple ffmpeg binaries are detected
### Scope
On startup, warn if multiple ffmpeg binaries are present, which might cause conflicts or incompatibilities
Long Form
Multiple users are coming in to the discord with errors with transcoding, old versions etc... This all mostly comes down to, and is fixed by removing their local ffmpeg which can become outdated, doesn't have support etc... and letting the system ffmpeg do it's job. In the case of https://github.com/nerethos/docker-stash and https://github.com/feederbox826/stash-s6, this usually results in failing transcodes since the local old ffmpeg without hwaccel support is used
Examples
https://github.com/stashapp/stash/issues/5291 https://canary.discord.com/channels/559159668438728723/559159931505213440/1288626890449485924 https://canary.discord.com/channels/559159668438728723/559159931505213440/1288342167663808522