Enable MicroWakeWord by default.

This enables MWW by default. This has become more important since
HomeAssistant recently disabled offloaded WakeWord engines by default in
new Assist pipelines, ostensibly because "all" client devices now
support it.

Currently we are limited to just `hey_jarvis` until esphome/esphome#8655
lands in a release and enables dynamic configuration. This will be fully
implemented with the SuperSensor v2.0 coming later this month.

supersensor.yaml

@@ -371,16 +371,15 @@ interval:
             App.safe_reboot();
           }
 
-# Add optional microWakeWord support (on-device wake word)
-# Doesn't work well as of 2024-07-04 so leave disabled
-#micro_wake_word:
-#  model: hey_jarvis
-#  on_wake_word_detected:
-#    then:
-#      - voice_assistant.start:
-#          wake_word: !lambda return wake_word;
+micro_wake_word:
+  vad:
+  models:
+    - model: hey_jarvis
+  on_wake_word_detected:
+    then:
+      - voice_assistant.start:
+          wake_word: !lambda return wake_word;
 
-# Include the Espressif Audio Development Framework for VAD support
 esp_adf:
 external_components:
   - source: github://pr#5230