feat(can): Add CAN ID definitions

This commit introduces the CAN ID definitions for the irrigation system.
It defines the structure of the CAN IDs and macros for priority and function.
Signed-off-by: Eduard Iten <eduard@iten.pro>

software/include/lib/can_ids.h

@@ -0,0 +1,41 @@
+#ifndef CAN_IDS_H
+#define CAN_IDS_H
+
+/*
+CAN ID structure for the irrigation system.
+PPP FFFF NNNN
+
+PPP: Priority
+    000: Network segment
+    001: Critical error
+    010: Commands
+    100: Status messages
+    110: measurements
+    111: Info messages
+
+FFFF: Function
+    0001: Valve Commands
+    0010: Valve States
+    0011: IO Commands
+    0100: IO States
+    0101: Measurements
+    0111: Sysem Functions (e.g. reset, firmware update)
+
+NNNN: Node ID
+*/
+
+#define CAN_ID_PRIORITY_NETWORK 0x000
+#define CAN_ID_PRIORITY_CRITICAL_ERROR 0x100
+#define CAN_ID_PRIORITY_COMMANDS 0x200
+#define CAN_ID_PRIORITY_STATUS 0x400
+#define CAN_ID_PRIORITY_MEASUREMENTS 0x600
+#define CAN_ID_PRIORITY_INFO 0x700
+
+#define CAN_ID_FUNCTION_VALVE_COMMANDS 0x010
+#define CAN_ID_FUNCTION_VALVE_STATES 0x020
+#define CAN_ID_FUNCTION_IO_COMMANDS 0x030
+#define CAN_ID_FUNCTION_IO_STATES 0x040
+#define CAN_ID_FUNCTION_MEASUREMENTS 0x050
+#define CAN_ID_FUNCTION_SYSTEM_FUNCTIONS 0x070
+
+#endif // CAN_IDS_H