Add fire alarm handling for DC30 CCS main controller.

Latch fire alarm until reboot, block recovery commands, and send periodic Everest ESTOP while active.

Co-authored-by: Cursor <cursoragent@cursor.com>

Core/Src/serial_handler.c

@@ -4,6 +4,7 @@
 #include "board.h"
 #include "psu_control.h"
 #include "debug.h"
+#include "fire_alarm.h"
 #include <string.h>
 
 #ifdef USE_WEB_INTERFACE
@@ -27,6 +28,11 @@ void SC_CommandHandler(ReceivedCommand_t* cmd) {
     
     uint8_t response_code = RESP_FAILED;
 
+    if (FireAlarm_IsBlockingCommand(cmd->command)) {
+        SC_SendPacket(NULL, 0, RESP_FAILED);
+        return;
+    }
+
     switch (cmd->command) {
         // Команды БЕЗ аргументов
         case CMD_GET_STATUS:
@@ -86,6 +92,11 @@ void SC_CommandHandler(ReceivedCommand_t* cmd) {
             // }
             response_code = RESP_FAILED;
             break;
+        case CMD_FIRE_ALARM:
+            FireAlarm_Activate();
+            response_code = RESP_SUCCESS;
+            break;
+
         case CMD_DEVICE_RESET:
             // 2. Отправляем SUCCESS (хост может успеть получить его перед ребутом)
             SC_SendPacket(NULL, 0, RESP_SUCCESS);