Remove dead host esszimmerradio

The Pi is gone; the name no longer resolves. It was still picked up by
the "hosts: all" playbooks (update-packages.yml, test_keepass.yml),
where it showed up as unreachable on every fleet run.

It was also the only host pointing pi_squeezelite_squeezeserver at
192.168.178.100 (musicdolphin) rather than the central server at .80,
so nothing depends on musicdolphin's LMS instance any more.

The "esszimmer" rows in roles/bluetooth_monitor/other/*.csv and the
analysis notebook are room labels in historical sensor training data,
not this host, and are left alone.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

inventory.yml

@@ -13,14 +13,6 @@ all:
           sensor_room_name: prusaprinter
           pi_dhtsensor_dht_pin: 26
           main_user: root
-        esszimmerradio: # oben, eltern
-          squeezelite_name: Esszimmer
-          pi_shairport_name: _Oben_Esszimmer
-          # alsa_card_name: Device
-          pi_squeezelite_squeezeserver: 192.168.178.100
-          configure_wifi: true
-          alsa_card_name: 1
-          main_user: root
         newrpi:
           squeezelite_name: MyTestRaspberry
           pi_shairport_name: MyTestRaspberry