Customised Home Assistant media_player custom component for Pioneer AVRs. Tested on a VSX-930 (Main Zone and HDZone outputs).

Added support for the following features:

• Auto-detect and create entities for Zones 1, 2, 3 and HDZONE.
• Maintain single continuous telnet session to AVR, with automatic reconnect.
• Eliminate polling where AVR sends keepalive responses (on port 8102).
• Separated Pioneer API into a separate class, ready to be moved into a separate module to follow current Home Assistant integration standards.
• Automatically poll AVR for source names - no need to manually code them any more.
• Uses source names instead of source IDs for selecting a new source.
• Added workaround for AVRs with an initial volume set on the Main Zone. The initial volume is not reported correctly until a volume change is made on the AVR. The workaround sends volume_up, volume_down commands to correct the reported volume without affecting the initial volume setting.

NOTE: On the VSX-930, the telnet API can become very unstable when telnet connections are made to it repeatedly. The original component established a new telnet connection for each command sent to the AVR, including the commands used to poll status. This component reuses a single telnet connection, established at component start and re-established automaticlly if it disconnects, for both sending commands and receiving status updates that are then reflected in Home Assistant in real time.