fix(zigbee): Add lock in scanNetworks to avoid race condition

[P-R-O-C-H-Y]

Description of Change

Improvements to scan management and thread safety:

• Added a check to prevent initiating a new scan if one is already in progress, logging a warning and returning early in ZigbeeCore::scanNetworks (ZigbeeCore.cpp).
• Wrapped the scan request call with esp_zb_lock_acquire and esp_zb_lock_release to ensure thread safety when starting a Zigbee network scan (ZigbeeCore.cpp).

Test Scenarios

Tested using the ScanNetworks example.

Related links

Closes #10879

[github-actions]

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Generated by 🚫 dangerJS against 91ba3b5

[github-actions]

Test Results

 76 files   76 suites   13m 12s ⏱️
 38 tests  38 ✅ 0 💤 0 ❌
241 runs  241 ✅ 0 💤 0 ❌

Results for commit 91ba3b5.

♻️ This comment has been updated with latest results.

[github-actions]

Memory usage test (comparing PR against master branch)

The table below shows the summary of memory usage change (decrease - increase) in bytes and percentage for each target.

Memory	FLASH [bytes]		FLASH [%]		RAM [bytes]		RAM [%]
Target	DEC	INC	DEC	INC	DEC	INC	DEC	INC
ESP32C5	0	0	0.00	0.00	0	0	0.00	0.00
ESP32S3	0	0	0.00	0.00	0	0	0.00	0.00
ESP32S2	0	0	0.00	0.00	0	0	0.00	0.00
ESP32C3	0	0	0.00	0.00	0	0	0.00	0.00
ESP32C6	0	0	0.00	0.00	0	0	0.00	0.00
ESP32H2	0	0	0.00	0.00	0	0	0.00	0.00
ESP32	0	0	0.00	0.00	0	0	0.00	0.00

Click to expand the detailed deltas report [usage change in BYTES]

Target	ESP32C5		ESP32S3		ESP32S2		ESP32C3		ESP32C6		ESP32H2		ESP32
Example	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM
libraries/Zigbee/examples/Zigbee_Analog_Input_Output	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Binary_Input	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_CarbonDioxide_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Color_Dimmable_Light	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Color_Dimmer_Switch	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Contact_Switch	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Dimmable_Light	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Electrical_AC_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Electrical_AC_Sensor_MultiPhase	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Electrical_DC_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Fan_Control	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Gateway	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Illuminance_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_OTA_Client	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Occupancy_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_On_Off_Light	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_On_Off_MultiSwitch	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_On_Off_Switch	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_PM25_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Power_Outlet	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Pressure_Flow_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Range_Extender	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Scan_Networks	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Temp_Hum_Sensor_Sleepy	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Temperature_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Thermostat	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Vibration_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Wind_Speed_Sensor	-	-	-	-	-	-	-	-	-	-	-	-	-	-
libraries/Zigbee/examples/Zigbee_Window_Covering	-	-	-	-	-	-	-	-	-	-	-	-	-	-