feat: add AE/AWB lock test functionality and related services

orbbec_camera/examples/ae_awb_lock/README.md

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+# AE/AWB Lock Test
+
+This sample exposes a test-only ROS 2 action that verifies the AE/AWB capture and manual
+lock-in flow through the camera driver's services.
+
+Run the camera driver and this sample in the same namespace:
+
+```bash
+ros2 run orbbec_camera ae_awb_lock_test_node --ros-args -r __ns:=/camera
+```
+
+Send a goal and print feedback:
+
+```bash
+ros2 action send_goal \
+  /camera/run_ae_awb_lock_test \
+  orbbec_camera_msgs/action/RunAeAwbLockTest \
+  "{timeout_ms: 10000}" \
+  --feedback
+```
+
+The sample enables auto exposure and auto white balance, waits until the SDK status equals `1`,
+captures the current exposure, color gain, AWB gains, and color temperature, disables the auto
+controls, and writes the captured values back in this order:
+
+1. Color exposure
+2. Color gain
+3. AWB R/B/G gains
+4. Color temperature
+
+The final AWB gain readback must exactly match the captured value. Other readback differences are
+reported as warnings because the device may quantize those controls. On failure or cancellation,
+the sample restores auto exposure and auto white balance.
+
+Every feedback phase contains a fresh status value read from the camera service. The
+`waiting_for_services` feedback is published after all required services become available, because
+the status cannot be read before its service is ready.