Local develop setup with docker (#1103)

* Add local live kit backend run setup

.env.example

@@ -3,6 +3,9 @@
 # Environment files are documented here:
 # https://vitejs.dev/guide/env-and-mode.html#env-files
 ####
+# Develop backend settings:
+LIVEKIT_KEY="devkey"
+LIVEKIT_SECRET="secret"
 
 # Used for determining the homeserver to use for short urls etc.
 # VITE_FALLBACK_STUN_ALLOWED=false