fix: resolve issue-facade ID mapping bugs and enhance functionality

- Fix Sentinel bug in list command where Click set search params to Sentinel.UNSET
- Fix version command by adding explicit version and package_name parameters
- Fix test isolation by correcting mock patch targets and datetime objects
- Fix critical ID mapping bug: use issue.number consistently instead of mixing with issue.backend_id
- Update all comment operations to use issue numbers instead of internal IDs
- Ensure issue-facade uses upstream issue numbers directly without local ID confusion
- Add comprehensive test coverage with 20 passing tests
- Verify core functionality: list, show, close, version, backend management all working
- Successfully close issue #166 with proper comment handling

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

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

issue_tracker/cli/main.py

@@ -0,0 +1,118 @@
+"""
+Main CLI Entry Point
+
+Universal Issue Tracking System CLI
+"""
+
+import click
+import sys
+from pathlib import Path
+
+from .commands import issue_group
+from .backend_commands import backend_group
+from .sync_commands import sync_group
+from .. import __version__
+
+
+@click.group()
+@click.version_option(version=__version__, package_name='issue-tracker')
+@click.option('--config', type=click.Path(), help='Configuration file path')
+@click.option('--backend', help='Backend to use (local, gitea)')
+@click.option('--verbose', '-v', is_flag=True, help='Verbose output')
+@click.pass_context
+def cli(ctx, config, backend, verbose):
+    """
+    Universal Issue Tracking System
+
+    A backend-agnostic issue tracking tool that works with local SQLite,
+    Gitea, GitHub, and other issue tracking systems.
+
+    Examples:
+        issue list                    # List all issues
+        issue create "Bug in parser"  # Create new issue
+        issue show 42                 # Show issue #42
+        issue close 42                # Close issue #42
+
+        backend add local ~/.issues   # Add local backend
+        backend add gitea myrepo      # Add Gitea backend
+
+        sync pull gitea               # Sync from Gitea
+        sync push gitea               # Sync to Gitea
+    """
+    # Ensure the object exists
+    ctx.ensure_object(dict)
+
+    # Store global options in context
+    ctx.obj['config_path'] = config
+    ctx.obj['backend'] = backend
+    ctx.obj['verbose'] = verbose
+
+
+# Register command groups
+cli.add_command(issue_group, name='issue')
+cli.add_command(backend_group, name='backend')
+cli.add_command(sync_group, name='sync')
+
+
+# Convenience aliases - direct issue commands
+@cli.command('list')
+@click.pass_context
+def list_issues(ctx):
+    """List all issues (alias for 'issue list')."""
+    ctx.invoke(issue_group.get_command(ctx, 'list'))
+
+
+@cli.command('show')
+@click.argument('issue_number', type=int)
+@click.pass_context
+def show_issue(ctx, issue_number):
+    """Show issue details (alias for 'issue show')."""
+    ctx.invoke(issue_group.get_command(ctx, 'show'), issue_number=issue_number)
+
+
+@cli.command('create')
+@click.argument('title')
+@click.option('--description', '-d', help='Issue description')
+@click.option('--label', '-l', multiple=True, help='Labels to add')
+@click.option('--assignee', '-a', help='Assign to user')
+@click.option('--milestone', '-m', help='Milestone')
+@click.pass_context
+def create_issue(ctx, title, description, label, assignee, milestone):
+    """Create new issue (alias for 'issue create')."""
+    ctx.invoke(
+        issue_group.get_command(ctx, 'create'),
+        title=title,
+        description=description,
+        label=label,
+        assignee=assignee,
+        milestone=milestone
+    )
+
+
+@cli.command('close')
+@click.argument('issue_number', type=int)
+@click.option('--comment', '-c', help='Closing comment')
+@click.pass_context
+def close_issue(ctx, issue_number, comment):
+    """Close issue (alias for 'issue close')."""
+    ctx.invoke(
+        issue_group.get_command(ctx, 'close'),
+        issue_number=issue_number,
+        comment=comment
+    )
+
+
+def main():
+    """Main entry point for the CLI."""
+    try:
+        cli(obj={})
+    except KeyboardInterrupt:
+        click.echo("\nAborted by user", err=True)
+        sys.exit(1)
+    except Exception as e:
+        click.echo(f"Error: {e}", err=True)
+        sys.exit(1)
+
+
+if __name__ == '__main__':
+    main()