Seeking HA-integrated proximity sensor suggestions for a quiet dog (PoE available)

[delicate night]

I'm looking for a pre-built, Home Assistant-compatible solution to detect when my dog is waiting at the door. They don't bark; just sit silently and stare.

Prefers a collar-mounted tag or similar proximity sensor.

Range: ~3' radius from the door.

Infrastructure: I have PoE available at the location, leaning towards hardwire/WiFi/Bluetooth connectivity options for the monitor.

Prefer no DIY/custom builds (limited time, but open to it if needed) and no pet doors (I need to wipe paws manually).

Any suggestions for a "plug-and-play" sensor that integrates locally with HA?

[delicate night]

I'm thinking of deconstructing a pet door to use its prebuilt parts to fit my needs. Any suggestions?

[woeful lagoon]

i trained my dog to tap a button, but that's not exactly a time-saving option

are you looking for something outdoors, or on the interior side, or both?