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@@ -4,6 +4,27 @@ This diary tracks major work packages, events, and milestones in the MarkiTect p
 
 ---
 
+## 2025-09-24: Project Management System Implementation & Issue Lifecycle Enhancement
+
+**Progress:** Implemented comprehensive project management system with issue lifecycle support and milestone-based organization
+**Contributors:** User (bernd.worsch), Claude Code (Sonnet 4)
+**Time Estimate:** ~2-3 hours of research, implementation, and testing
+**AI Resources:** ~20-25 Claude Sonnet 4 conversations, estimated 40K+ tokens
+
+**PROJECT MANAGEMENT BREAKTHROUGH:** Successfully implemented complete project management system using Gitea's available features after discovering project boards are not universally available. Created `tddai/project_manager.py` with comprehensive milestone and label-based project organization. The system uses milestones as projects and labels for states (Todo, Active, Review, Done, Blocked) and priorities (Low, Medium, High, Critical), providing full project management capabilities within Gitea's API constraints.
+
+**ISSUE LIFECYCLE MANAGEMENT:** Enhanced the tddai framework with complete issue lifecycle support including state transitions, priority management, milestone assignment, and automatic issue closing for completed work. The ProjectManager class provides 15+ methods for milestone creation, label management, issue state transitions, and project overview reporting. Integrated with existing IssueWriter to provide comprehensive issue management through both direct API calls and CLI interface.
+
+**CLI INTERFACE EXPANSION:** Added 8 new CLI commands for complete project management workflow: `setup-project-mgmt`, `project-overview`, `set-issue-state`, `set-issue-priority`, `create-milestone`, `list-milestones`, `assign-to-milestone`. The CLI provides user-friendly state names (todo/active/review/done/blocked) and priority levels (low/medium/high/critical) with automatic enum conversion and comprehensive error handling.
+
+**AUTOMATED PROJECT SETUP:** Implemented `ensure_project_labels()` method that automatically creates all required project management labels with proper colors and descriptions. The system creates 13 standard labels covering all project states, priorities, and issue types (bug, feature, enhancement, documentation). This enables immediate project management capability on any Gitea repository with a single setup command.
+
+**FRAMEWORK INTEGRATION:** The project management system seamlessly integrates with existing tddai components including authentication patterns, error handling, and CLI design. Enhanced IssueWriter with project management methods (assign_to_milestone, add_labels, remove_labels) while maintaining backward compatibility. All project management operations use consistent API patterns and comprehensive error handling established in the framework.
+
+**PRACTICAL VALIDATION:** Successfully tested the complete project management system by creating the "CLI Implementation" milestone, setting up all required labels, assigning issues #12-#15 to the milestone, marking Issue #1 as completed and closed, and setting Issue #12 as active with high priority. The system properly tracks project progress with 1 active milestone containing 4 assigned issues, demonstrating real-world project management capability.
+
+---
+
 ## 2025-09-24: IssueCreator Implementation & CLI Roadmap Execution
 
 **Progress:** Implemented comprehensive issue creation system and successfully registered all CLI implementation issues in Gitea