Enhance IMU data visualization and file handling

- Updated `main.py` to include a flag for real GPIO output control.
- Added a new function in `visualise.py` to generate unique file paths for CSV and plot outputs by appending timestamps if the file already exists.
- Modified CSV and plot saving logic to utilize the new unique path function, ensuring no overwriting of existing files.
- Introduced a new image file `imu_quality_20260701_131902.png` and updated the existing `imu_quality.png`.

main.py

@@ -69,6 +69,15 @@ raw_values = [0] * 10
 
 
 # ---------------- DOUT TEST MODE ----------------
+# False:
+#   Only update software DOUT state in outgoing packet.
+#   GPIO18/GPIO19 will NOT really change.
+#
+# True:
+#   Actually drive GPIO18/GPIO19.
+#
+# Start with False. If o/c/s changes DOUT in pc_reader output,
+# then set it to True and test real hardware.
 
 USE_REAL_DOUT = True