refactor: remove obsolete issue management system in favor of issue-facade

Complete cleanup of the legacy TDD AI and issue management system, establishing clear separation of concerns as requested. All issue handling is now provided by the standalone issue-facade system.

Removed components:
- TDD AI framework (tddai/ directory and tddai_cli.py)
- Legacy issue management CLI commands and services
- Issue-related Makefile targets and helper commands
- Obsolete tests and infrastructure dependencies
- Finance modules that depended on the old issue system

Updated:
- Makefile: Removed issue-*, tdd-*, and test-from-issue commands
- CLI framework: Simplified to core functionality only
- Documentation: Added deprecation notice for old config system

The issue-facade now serves as the universal CLI for issue tracking,
providing backend-agnostic interface to GitHub, GitLab, Gitea, and
local SQLite storage as documented in issue-facade/README.md.

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

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

cli/commands/__init__.py

@@ -5,16 +5,8 @@ Commands handle argument parsing and delegation to services.
 They contain no business logic, only CLI-specific concerns.
 """
 
-from .workspace import WorkspaceCommands
-from .issues import IssueCommands
-from .project import ProjectCommands
-from .export import ExportCommands
 from .config import ConfigCommands
 
 __all__ = [
-    'WorkspaceCommands',
-    'IssueCommands',
-    'ProjectCommands',
-    'ExportCommands',
     'ConfigCommands'
 ]