Implement Planner Subagent

[prosdev]

Description

Implement a planner subagent that can analyze GitHub issues and break them down into actionable tasks. This will assist developers in planning their work efficiently.

Acceptance Criteria

• Planner can analyze GitHub issues using GitHub CLI
• Task breakdown logic identifies individual steps
• Plans are visualized clearly for users
• Planner handles complex issues correctly
• System integrates with the subagent coordinator

Technical Requirements

• Implement GitHub CLI integration for issue analysis
• Create task breakdown algorithms
• Define clear interfaces for plans and tasks
• Implement visualization of plans
• Support for different planning strategies
• Integration with the subagent coordinator

Branch: feat/planner-subagent
Priority: Medium
Estimate: 3 days
Parent Epic: #2