style: apply ruff auto-fixes across codebase

- Fix import sorting (isort) across all engine modules
- Fix SIM105 try-except-pass patterns (contextlib.suppress)
- Fix nested with statements in tests
- Fix unused loop variables

Run 'uv run pytest' to verify tests still pass.

engine/config.py

@@ -3,8 +3,8 @@ Configuration constants, CLI flags, and glyph tables.
 """
 
 import sys
-
 from pathlib import Path
+
 _REPO_ROOT = Path(__file__).resolve().parent.parent
 _FONT_EXTENSIONS = {".otf", ".ttf", ".ttc"}