Release 0.4.2

Final stability fixes after 0.4.1: Model Error leaves out spans with
unknown inputs; window sensors unknown at startup stay unknown, with last
known states restored as unknown across restarts; unload, reload and
removal can no longer publish stale results or recreate a deleted model;
Forecast Error scores only forecasts whose plan the relay matched within
2 minutes. Adds Reset learned model to Configure. Still observation-only.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

custom_components/heating_mpc/manifest.json

@@ -9,5 +9,5 @@
   "iot_class": "local_polling",
   "requirements": [],
   "single_config_entry": true,
-  "version": "0.4.1"
+  "version": "0.4.2"
 }