[TASK] Mission Start Condition Node

[jorgenfj]

Description of task

Description

Create a reusable Behavior Tree Condition node that gates mission execution until a /mission/start ROS 2 service accepts a mission start request.

This node will be used at the root of mission behavior trees to ensure that no mission logic executes until an external supervisor explicitly starts a mission. The implementation must be reusable across multiple missions and independent of mission-specific logic.

---

Motivation

• Missions should not begin automatically when the BT starts ticking
• Mission start should be externally controlled (UI, operator, autonomy supervisor)
• The same mission-start mechanism must work for all missions
• BT mission logic should remain declarative and reusable

---

Proposed Solution

Implement a new BT Condition node that will:

• Act as a gate at the root of the behavior tree
• Cache the result internally
• Expose the accepted mission ID via the BT blackboard

Suggested Workflow

No response

Specifications

No response

Contacts

No response

Code Quality

• Every function in header files are documented (inputs/returns/exceptions)
• The project has automated tests that cover MOST of the functions and branches in functions (pytest/gtest)
• The code is documented on the wiki (provide link)