Miscellaneous fixes (0.18) (#24567)

* run recording snapshot ffmpeg off the event loop

The recording snapshot and Frigate+ recording submit endpoints called get_image_from_recording inline, which is a blocking ffmpeg subprocess with no timeout, so every other request stalled until the frame was decoded. Both calls now run in asyncio.to_thread.

* fix camera info dialog overflowing on mobile

* adjust test

web/src/components/overlay/CameraInfoDialog.tsx

@@ -91,7 +91,7 @@ export default function CameraInfoDialog({
         open={showCameraInfoDialog}
         onOpenChange={setShowCameraInfoDialog}
       >
-        <DialogContent>
+        <DialogContent className="scrollbar-container max-h-[90dvh] overflow-y-auto">
           <DialogHeader>
             <DialogTitle className="smart-capitalize">
               {t("cameras.info.cameraProbeInfo", {