Add ROS2 message for changing tasks

ros/angel_msgs/msg/SystemCommands.msg

@@ -8,8 +8,39 @@
 # received message instance.
 #
 
+
+# =====================
 # Task Monitor commands
+# =====================
+
+# Index of GSP tasks being concurrently handled to indicate step progression/regression for.
 int8 task_index
+
+# If the current task progress should be reset.
 bool reset_current_task
+
+# If the current task progress should be regressed a step,
 bool previous_step
+
+# If the current task progress should be progressed a step.
 bool next_step
+
+
+# =============
+# Task Changing
+# =============
+
+# Enumeration of sorts for the tasks that may be switched to.
+#
+# This is an enumeration here in order to be a source of coordination between
+# nodes that support this functionality as just simply passing a string can
+# easily be subject to spelling errors or misalignment between nodes.
+#
+uint32 TASK_NO_CHANGE   =   0
+uint32 TASK_COOKING     =   1   # Cooking is "meta" atm because it is multi-task under the hood.
+uint32 TASK_MEDICAL_M2  =   2
+uint32 TASK_MEDICAL_M3  =   3
+uint32 TASK_MEDICAL_R18 =   4
+
+# The task that is being changed to.
+uint32 change_task