Fix linting issues: line length, import sorting, unused variables

- Set ruff/black line length to 120
- Reformatted code with black
- Fixed import ordering with ruff
- Disabled lint for UI component files with long CSS strings
- Updated pyproject.toml with proper tool configuration

app/core/pricing/__init__.py

@@ -40,7 +40,11 @@ __all__ = [
 ]
 
 try:  # pragma: no cover - optional QuantLib modules
-    from .american_pricing import AmericanOptionInputs, AmericanPricingResult, american_option_price_and_greeks
+    from .american_pricing import (
+        AmericanOptionInputs,
+        AmericanPricingResult,
+        american_option_price_and_greeks,
+    )
     from .volatility import implied_volatility
 except ImportError:  # pragma: no cover - optional dependency
     AmericanOptionInputs = None