feat: Implement comprehensive project management system with issue lifecycle support

- Add ProjectManager with milestone and label-based project organization
- Support project states (Todo, Active, Review, Done, Blocked) via labels
- Add priority management (Low, Medium, High, Critical) with label integration
- Implement milestone creation and management for project tracking
- Enhance IssueWriter with project management methods (assign_to_milestone, add/remove_labels)
- Add 8 new CLI commands for complete project management workflow
- Support automatic project management setup with ensure_project_labels()
- Enable issue state transitions with automatic closing for completed issues
- Integrate with existing Gitea API authentication and error handling patterns

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

tddai/__init__.py

@@ -8,6 +8,7 @@ Provides workspace management, test generation, and issue integration.
 from .workspace import WorkspaceManager, Workspace, WorkspaceStatus
 from .issue_fetcher import IssueFetcher, Issue
 from .issue_creator import IssueCreator
+from .project_manager import ProjectManager, ProjectState, Priority
 from .test_generator import TestGenerator
 from .coverage_analyzer import CoverageAnalyzer, CoverageAssessment, TestRequirement, CoverageGap
 from .exceptions import TddaiError, WorkspaceError, IssueError, ConfigurationError, TestGenerationError
@@ -20,6 +21,9 @@ __all__ = [
     "IssueFetcher",
     "Issue",
     "IssueCreator",
+    "ProjectManager",
+    "ProjectState",
+    "Priority",
     "TestGenerator",
     "CoverageAnalyzer",
     "CoverageAssessment",