Add fully local conversational AI pipeline for Reachy Mini

Local STT (Qwen3-ASR), VLM (Gemma 4 26B-A4B), and TTS (Spark-TTS) running
on Apple Silicon via MLX, with bracket-tag action system for nod, shake,
wiggle, dance, photo, and pre-recorded emotions.

test_reachy.py

@@ -0,0 +1,10 @@
+from reachy_mini import ReachyMini
+
+with ReachyMini(localhost_only=False, media_backend='no_media') as mini:
+    print("Connected to Reachy Mini!")
+
+    # Wiggle antennas
+    print("Wiggling antennas...")
+    mini.goto_target(antennas=[0.5, -0.5], duration=0.5)
+    mini.goto_target(antennas=[-0.5, 0.5], duration=0.5)
+    mini.goto_target(antennas=[0, 0], duration=0.5)