VesiScan BASIC origin: Piezo + IMU firmware initial code

- nRF52840 + SoftDevice S140 BLE firmware
- Piezo ultrasound TX driver (2MHz, 8ch MUX)
- ICM42670P IMU 6-axis driver
- Echo AFE chain (ADA2200 + ADC121S051)
- BLE NUS command parser (mpa/mpc/mdc/mec/maa/msp)
- FDS flash config storage
- pc_firm parser and ADC driver included

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pc_firm/ble_security/ble_quick_security.h

@@ -0,0 +1,56 @@
+ /**
+ * @file ble_quick_security.h
+ * @brief Ultra-simple BLE Security Configuration
+ * 
+ * ONE function call to control entire security behavior.
+ * Works with existing debug_print.h system.
+ */
+
+#ifndef BLE_QUICK_SECURITY_H
+#define BLE_QUICK_SECURITY_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "peer_manager.h"
+
+/**
+ * @brief Initialize BLE security with ONE simple parameter
+ * 
+ * @param[in] development_mode  true (1) = Fast development (no security)
+ *                              false (0) = Production (full security)
+ * 
+ * Development mode (1):
+ *   - No pairing/bonding required
+ *   - Auto-deletes all bonds on startup
+ *   - Instant connection
+ *   - Fast iteration
+ * 
+ * Production mode (0):
+ *   - Full security with passkey
+ *   - Bonding preserved
+ *   - MITM protection
+ *   - Secure deployment
+ * 
+ * Usage in main.c:
+ *   #define BLE_DEV_MODE 1  // or 0
+ *   ble_security_quick_init(BLE_DEV_MODE);
+ */
+void ble_security_quick_init(bool development_mode);
+
+/**
+ * @brief Get current mode
+ * @return true if in development mode, false if production
+ */
+bool ble_security_is_dev_mode(void);
+
+/**
+ * @brief Peer Manager event handler
+ * 
+ * Call this from your pm_evt_handler() function.
+ * It handles all security events automatically.
+ * 
+ * @param[in] p_evt  Peer Manager event
+ */
+void ble_security_quick_pm_handler(pm_evt_t const *p_evt);
+
+#endif // BLE_QUICK_SECURITY_H