feat(valve): Implement obstacle detection with configurable thresholds

Introduces separate configurable current thresholds for obstacle detection
during valve opening and closing movements.

- Added  state to .
- Added  and
   to .
- Modified  to implement obstacle detection in ,
  setting  on high current, and to load/save
  these new thresholds via settings.
- Added new setter/getter functions for obstacle thresholds to  and .
- Updated  with new shell commands (, )
  and updated  to display these settings.
- Updated  to document the new registers and error states.
- Updated  to include new register definitions, menu options,
  and display of obstacle current thresholds.

software/include/lib/modbus_server.h

@@ -89,9 +89,21 @@ enum {
 	 */
 	REG_HOLDING_MAX_CLOSING_TIME_S = 0x0002,
 	/**
-	 * @brief Minimum current threshold in mA for end-position detection.
+	 * @brief Minimum current threshold in mA for end-position detection during opening.
 	 */
-	REG_HOLDING_VALVE_END_CURRENT_THRESHOLD_MA = 0x0003,
+	REG_HOLDING_END_CURRENT_THRESHOLD_OPEN_MA = 0x0003,
+	/**
+	 * @brief Minimum current threshold in mA for end-position detection during closing.
+	 */
+	REG_HOLDING_END_CURRENT_THRESHOLD_CLOSE_MA = 0x0004,
+	/**
+	 * @brief Obstacle current threshold in mA for opening.
+	 */
+	REG_HOLDING_OBSTACLE_CURRENT_THRESHOLD_OPEN_MA = 0x0005,
+	/**
+	 * @brief Obstacle current threshold in mA for closing.
+	 */
+	REG_HOLDING_OBSTACLE_CURRENT_THRESHOLD_CLOSE_MA = 0x0006,
 	/**
 	 * @brief Bitmask for reading and writing digital outputs. Bit 0: Output 1,
 	 * Bit 1: Output 2. 1=ON, 0=OFF.