refactor: move wingman to src/ with linting fixes

[Chesars]

Description

Fixed linting errors in src/wingman/ directory from PR #6.

Details

• Organized and cleaned up imports (removed unused imports)
• Removed unnecessary f-string prefixes
• Simplified code structure (combined nested ifs, replaced try-except-pass with contextlib.suppress)
• Used more pythonic patterns (enumerate instead of manual counter, ternary operators)
• Fixed ambiguous variable name (l → line)

All changes are style-only and preserve existing behavior. No logic changes.

✅ uv run ruff check src/wingman/     # All checks passed!
✅ uv run ruff format --check src/wingman/  # 15 files already formatted

Type of Change

• Refactoring (no functional changes)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• My changes generate no new warnings
• I have tested the TUI locally