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.

tests/test_terminal.py

@@ -14,21 +14,25 @@ class TestTerminalDimensions:
 
     def test_tw_returns_columns(self):
         """tw() returns terminal width."""
-        with patch.object(sys.stdout, "isatty", return_value=True):
-            with patch("os.get_terminal_size") as mock_size:
-                mock_size.return_value = io.StringIO("columns=120")
-                mock_size.columns = 120
-                result = terminal.tw()
-                assert isinstance(result, int)
+        with (
+            patch.object(sys.stdout, "isatty", return_value=True),
+            patch("os.get_terminal_size") as mock_size,
+        ):
+            mock_size.return_value = io.StringIO("columns=120")
+            mock_size.columns = 120
+            result = terminal.tw()
+            assert isinstance(result, int)
 
     def test_th_returns_lines(self):
         """th() returns terminal height."""
-        with patch.object(sys.stdout, "isatty", return_value=True):
-            with patch("os.get_terminal_size") as mock_size:
-                mock_size.return_value = io.StringIO("lines=30")
-                mock_size.lines = 30
-                result = terminal.th()
-                assert isinstance(result, int)
+        with (
+            patch.object(sys.stdout, "isatty", return_value=True),
+            patch("os.get_terminal_size") as mock_size,
+        ):
+            mock_size.return_value = io.StringIO("lines=30")
+            mock_size.lines = 30
+            result = terminal.th()
+            assert isinstance(result, int)
 
     def test_tw_fallback_on_error(self):
         """tw() falls back to 80 on error."""
@@ -84,9 +88,11 @@ class TestTypeOut:
     @patch("time.sleep")
     def test_type_out_uses_color(self, mock_sleep):
         """type_out applies color codes."""
-        with patch("sys.stdout", new_callable=io.StringIO):
-            with patch("random.random", return_value=0.5):
-                terminal.type_out("Test", color=terminal.G_HI)
+        with (
+            patch("sys.stdout", new_callable=io.StringIO),
+            patch("random.random", return_value=0.5),
+        ):
+            terminal.type_out("Test", color=terminal.G_HI)
 
 
 class TestSlowPrint: