Add ability to restream birdseye (#4761)

* Try using RTSP for restream

* Add ability to get snapshot of birdseye when birdseye restream is enabled

* Write to pipe instead of encoding mpeg1

* Write to cache instead

* Use const for location

* Formatting

* Add hardware encoding for birdseye based on ffmpeg preset

* Provide framerate

* Adjust args

* Fix order

* Delete pipe file if it exists

* Cleanup spacing

* Fix spacing

frigate/config.py

@@ -519,6 +519,7 @@ class RestreamConfig(FrigateBaseModel):
     force_audio: bool = Field(
         default=True, title="Force audio compatibility with the browser."
     )
+    birdseye: bool = Field(default=False, title="Restream the birdseye feed via RTSP.")
     jsmpeg: JsmpegStreamConfig = Field(
         default_factory=JsmpegStreamConfig, title="Jsmpeg Stream Configuration."
     )