feat: Add MCP API for managing JIRA issue transitions/status changes

[dmikushin]

Summary

This PR adds comprehensive MCP API support for managing JIRA issue status transitions, eliminating the need to open the JIRA web interface for status changes.

Problem

Currently, users need to leave their development environment and open the JIRA web interface just to change an issue's status (e.g., from "To Do" to "In Progress" or marking as "Done"). This context switching is inefficient and disrupts workflow.

Solution

This PR introduces two new MCP tools that enable direct status management:

New Tools

1. jira_get_issue_transitions - Retrieves all available workflow transitions for an issue

   • Shows which status changes are possible from current state
   • Lists required/optional fields for each transition
   • Provides transition IDs needed for status changes

2. jira_transition_issue - Changes an issue's status

   • Supports workflow transitions with transition ID
   • Allows adding comments during transition
   • Handles required fields if workflow demands them
   • Supports bulk field updates during transition

Implementation Details

• Added getTransitions() and transitionIssue() methods to the issues service
• Created dedicated controller with proper error handling
• Implemented user-friendly formatter for transition information
• Full test coverage for all new functionality
• TypeScript types for type safety

Usage Examples

# Get available transitions for an issue
jira_get_issue_transitions --issueIdOrKey "PROJECT-123"

# Change issue status with comment
jira_transition_issue --issueIdOrKey "PROJECT-123" --transitionId "21" --comment "Starting work on this"

# Transition with field updates
jira_transition_issue --issueIdOrKey "PROJECT-123" --transitionId "31" --fields '{"resolution": {"id": "10000"}}'

Testing

• ✅ All existing tests pass
• ✅ New tests added for transitions controller and formatter
• ✅ TypeScript compilation successful
• ✅ Manual testing completed with real JIRA instance

Benefits

• Improved Developer Experience: No need to leave IDE/terminal to manage issue statuses
• Automation Ready: Can be integrated into scripts and workflows
• Consistent Interface: Uses same MCP patterns as other tools in the package
• Comprehensive: Handles all aspects of JIRA workflow transitions

This enhancement significantly improves the developer workflow by keeping all JIRA interactions within the development environment.