Rebuild firmware scaffold for ESP32-C6/ESP-IDF, replacing NCS/Zephyr

The product pivoted away from a Matter-first nRF54L15 device to an
ESP32-C6/ESP-IDF/C++17 platform where behaviour is defined by a
Blockly-generated Lua program instead of custom firmware (see the
updated kvida meta-repo vision). Removes the west/NCS/Zephyr scaffold
and replaces it with:

- A pinned ESP-IDF v6.0.2 Docker build environment (Espressif's
  official image already bundles the toolchain, unlike NCS/west).
- A layered component structure (drivers -> sensors -> profiles ->
  lua_runtime -> transport) matching the new architecture principles,
  with per-component READMEs describing responsibilities.
- An A/B OTA + LittleFS partition table and a minimal main.cpp.

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

docker-compose.yml

@@ -3,23 +3,25 @@ services:
     build:
       context: .
       dockerfile: docker/Dockerfile
-    working_dir: /workspace
+    working_dir: /project
+    environment:
+      - IDF_TARGET=esp32c6
     volumes:
-      # West workspace topdir: holds .west/, and the NCS/Zephyr module
-      # tree fetched by `west update` (nrf/, zephyr/, modules/, ...).
-      - ncs-workspace:/workspace
-      # This repo, bind-mounted as the manifest project inside the
-      # workspace (matches `self.path: kvida-os` in west.yml).
-      - .:/workspace/kvida-os
+      # Project source, bind-mounted.
+      - .:/project
+      # Build output and IDF Component Registry cache, kept in named
+      # volumes so they survive across container runs without polluting
+      # the bind-mounted source tree.
+      - build-cache:/project/build
+      - managed-components-cache:/project/managed_components
     tty: true
-    # USB/J-Link access (for `west flash`) is expected to be handled via
-    # usbipd-win forwarding the probe into WSL2. If `west flash` needs to
-    # run inside this container rather than on the WSL2 host, uncomment
-    # and adjust one of the following once the forwarded device node is
-    # known:
+    # USB access (for `idf.py flash`/`monitor`) is expected to be handled
+    # via usbipd-win forwarding the board's serial port into WSL2. If
+    # flashing needs to run inside this container rather than on the WSL2
+    # host, uncomment and adjust once the forwarded device node is known:
     # devices:
-    #   - "/dev/bus/usb:/dev/bus/usb"
-    # privileged: true
+    #   - "/dev/ttyUSB0:/dev/ttyUSB0"
 
 volumes:
-  ncs-workspace:
+  build-cache:
+  managed-components-cache: