Initial scaffold: ESP32-P4 firmware + voice gateway for Tatlock endpoint

DeskLock gives the Tatlock butler a face and voice on a Waveshare
ESP32-P4-WIFI6-Touch-LCD-3.4C round display in the living room.

- firmware/: ESP-IDF project targeting esp32p4 with the Waveshare XC BSP
- gateway/: FastAPI voice bridge (faster-whisper STT, Tatlock chat, Piper TTS)
- docs/architecture.md: component design and device<->gateway WS protocol

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,23 @@
+# ESP-IDF
+firmware/build/
+firmware/managed_components/
+firmware/sdkconfig
+firmware/sdkconfig.old
+firmware/dependencies.lock
+firmware/secrets.h
+
+# Python
+__pycache__/
+*.pyc
+.venv/
+.pytest_cache/
+.ruff_cache/
+.mypy_cache/
+*.egg-info/
+dist/
+
+# Editors / OS
+.vscode/
+.idea/
+*.swp
+.DS_Store