refactor: make beam work without `AppOrProxyId` #2910

Job	Run time
build-with-samply / Security, License Check	20s
build-with-samply / Build (amd64, sockets)	2m 0s
build-with-samply / Build (amd64)	1m 47s
build-with-samply / Cargo fmt check	0s
build-with-samply / Test (sockets)	1m 8s
build-with-samply / Test	1m 6s
build-with-samply / Docker (beam-broker) / Tidy GHCR images (samply/beam-broker)	22s
build-with-samply / Docker (beam-broker) / Dockerize (beam-broker)	50s
build-with-samply / Docker (beam-broker, sockets) / Tidy GHCR images (samply/beam-broker)	25s
build-with-samply / Docker (beam-broker, sockets) / Dockerize (beam-broker) (-sockets)	59s
build-with-samply / Docker (beam-proxy) / Tidy GHCR images (samply/beam-proxy)	21s
build-with-samply / Docker (beam-proxy) / Dockerize (beam-proxy)	58s
build-with-samply / Docker (beam-proxy, sockets) / Tidy GHCR images (samply/beam-proxy)	26s
build-with-samply / Docker (beam-proxy, sockets) / Dockerize (beam-proxy) (-sockets)	54s
	11m 36s

Provide feedback