Add stt entity (#91230)

* Add stt entity

* Update demo platform

* Rename ProviderEntity to SpeechToTextEntity

* Fix get method

* Run all init tests for config entry setup

* Fix and test metadata from header

* Test config entry unload

* Rename get provider entity

* Test post for non existing provider

* Test entity name before addition

* Test restore state

* Use register shutdown

* Update deprecation comment

homeassistant/components/demo/stt.py

@@ -13,8 +13,11 @@ from homeassistant.components.stt import (
     SpeechMetadata,
     SpeechResult,
     SpeechResultState,
+    SpeechToTextEntity,
 )
+from homeassistant.config_entries import ConfigEntry
 from homeassistant.core import HomeAssistant
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
 
 SUPPORT_LANGUAGES = ["en", "de"]
@@ -29,6 +32,60 @@ async def async_get_engine(
     return DemoProvider()
 
 
+async def async_setup_entry(
+    hass: HomeAssistant,
+    config_entry: ConfigEntry,
+    async_add_entities: AddEntitiesCallback,
+) -> None:
+    """Set up Demo speech platform via config entry."""
+    async_add_entities([DemoProviderEntity()])
+
+
+class DemoProviderEntity(SpeechToTextEntity):
+    """Demo speech API provider entity."""
+
+    @property
+    def supported_languages(self) -> list[str]:
+        """Return a list of supported languages."""
+        return SUPPORT_LANGUAGES
+
+    @property
+    def supported_formats(self) -> list[AudioFormats]:
+        """Return a list of supported formats."""
+        return [AudioFormats.WAV]
+
+    @property
+    def supported_codecs(self) -> list[AudioCodecs]:
+        """Return a list of supported codecs."""
+        return [AudioCodecs.PCM]
+
+    @property
+    def supported_bit_rates(self) -> list[AudioBitRates]:
+        """Return a list of supported bit rates."""
+        return [AudioBitRates.BITRATE_16]
+
+    @property
+    def supported_sample_rates(self) -> list[AudioSampleRates]:
+        """Return a list of supported sample rates."""
+        return [AudioSampleRates.SAMPLERATE_16000, AudioSampleRates.SAMPLERATE_44100]
+
+    @property
+    def supported_channels(self) -> list[AudioChannels]:
+        """Return a list of supported channels."""
+        return [AudioChannels.CHANNEL_STEREO]
+
+    async def async_process_audio_stream(
+        self, metadata: SpeechMetadata, stream: AsyncIterable[bytes]
+    ) -> SpeechResult:
+        """Process an audio stream to STT service."""
+
+        # Read available data
+        async for _ in stream:
+            pass
+
+        return SpeechResult("Turn the Kitchen Lights on", SpeechResultState.SUCCESS)
+
+
 class DemoProvider(Provider):
     """Demo speech API provider."""