Miscellaneous fixes (0.18 beta) (#23934)

* add host npu requirements to docs

* allow toggling live audio transcription via mqtt

* improve spacing consistency on mobile drawers

* fix clearing the region grid not surviving a restart

docs/docs/configuration/object_detectors.md

@@ -297,6 +297,14 @@ detectors:
 
 :::
 
+### Intel NPU host requirements {#intel-npu-requirements}
+
+The NPU firmware is loaded by the host kernel and is not part of the Frigate image. Everything else the NPU needs is bundled in the container, so host NPU libraries should never be mounted in.
+
+Frigate bundles a specific version of Intel's [linux-npu-driver](https://github.com/intel/linux-npu-driver/releases), and the host firmware must come from that release or a newer one. Firmware older than the bundled driver may fail with `MAPPED_INFERENCE_VERSION is NOT compatible with the ELF`, where `Expected` is the version the firmware supports and `received` is the version the bundled compiler produced. Distributions often package older firmware than the driver Frigate ships, so check the build date on the host with `sudo dmesg | grep -i vpu` and update it there if needed.
+
+Intel NPUs cannot be used under Home Assistant OS, which does not include the NPU firmware.
+
 ### Configuration {#configuration-openvino}
 
 <ModelConfigDropdown detectorTitle="OpenVINO" models={objectDetectorsModels.openvino.models} />