feat(validators): add noqa suppression support to security and performance validators

- Add centralized _is_noqa_suppressed() to BaseValidator with normalization
  (accepts both SEC001 and SEC-001 formats for ruff compatibility)
- Wire noqa support into all 21 security and 18 performance check functions
- Add ruff external config for SEC/PERF/MOD/EXC codes in pyproject.toml
- Convert all 280 Python noqa comments to dashless format (ruff-compatible)
- Add site/ to IGNORE_PATTERNS (excludes mkdocs build output)
- Suppress 152 false positive findings (test passwords, seed data, validator
  self-references, Apple Wallet SHA1, etc.)
- Security: 79 errors → 0, 60 warnings → 0
- Performance: 80 warnings → 77 (3 test script suppressions)
- Add proposal doc with noqa inventory and remaining findings recommendations

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/checkout/exceptions.py

@@ -12,7 +12,7 @@ from app.exceptions.base import (
 )
 
 
-class CheckoutValidationException(ValidationException):  # noqa: MOD-025
+class CheckoutValidationException(ValidationException):  # noqa: MOD025
     """Raised when checkout data validation fails."""
 
     def __init__(
@@ -29,7 +29,7 @@ class CheckoutValidationException(ValidationException):  # noqa: MOD-025
         self.error_code = "CHECKOUT_VALIDATION_FAILED"
 
 
-class CheckoutSessionNotFoundException(ResourceNotFoundException):  # noqa: MOD-025
+class CheckoutSessionNotFoundException(ResourceNotFoundException):  # noqa: MOD025
     """Raised when checkout session is not found."""
 
     def __init__(self, session_id: str):
@@ -41,7 +41,7 @@ class CheckoutSessionNotFoundException(ResourceNotFoundException):  # noqa: MOD-
         )
 
 
-class CheckoutSessionExpiredException(BusinessLogicException):  # noqa: MOD-025
+class CheckoutSessionExpiredException(BusinessLogicException):  # noqa: MOD025
     """Raised when checkout session has expired."""
 
     def __init__(self, session_id: str):
@@ -52,7 +52,7 @@ class CheckoutSessionExpiredException(BusinessLogicException):  # noqa: MOD-025
         )
 
 
-class EmptyCheckoutException(ValidationException):  # noqa: MOD-025
+class EmptyCheckoutException(ValidationException):  # noqa: MOD025
     """Raised when trying to checkout with empty cart."""
 
     def __init__(self):
@@ -63,7 +63,7 @@ class EmptyCheckoutException(ValidationException):  # noqa: MOD-025
         self.error_code = "EMPTY_CHECKOUT"
 
 
-class PaymentRequiredException(BusinessLogicException):  # noqa: MOD-025
+class PaymentRequiredException(BusinessLogicException):  # noqa: MOD025
     """Raised when payment is required but not provided."""
 
     def __init__(self, order_total: float):
@@ -74,7 +74,7 @@ class PaymentRequiredException(BusinessLogicException):  # noqa: MOD-025
         )
 
 
-class PaymentFailedException(BusinessLogicException):  # noqa: MOD-025
+class PaymentFailedException(BusinessLogicException):  # noqa: MOD025
     """Raised when payment processing fails."""
 
     def __init__(self, reason: str, details: dict | None = None):
@@ -85,7 +85,7 @@ class PaymentFailedException(BusinessLogicException):  # noqa: MOD-025
         )
 
 
-class InvalidShippingAddressException(ValidationException):  # noqa: MOD-025
+class InvalidShippingAddressException(ValidationException):  # noqa: MOD025
     """Raised when shipping address is invalid or missing."""
 
     def __init__(self, message: str = "Invalid shipping address", details: dict | None = None):
@@ -97,7 +97,7 @@ class InvalidShippingAddressException(ValidationException):  # noqa: MOD-025
         self.error_code = "INVALID_SHIPPING_ADDRESS"
 
 
-class ShippingMethodNotAvailableException(BusinessLogicException):  # noqa: MOD-025
+class ShippingMethodNotAvailableException(BusinessLogicException):  # noqa: MOD025
     """Raised when selected shipping method is not available."""
 
     def __init__(self, shipping_method: str, reason: str | None = None):
@@ -111,7 +111,7 @@ class ShippingMethodNotAvailableException(BusinessLogicException):  # noqa: MOD-
         )
 
 
-class CheckoutInventoryException(BusinessLogicException):  # noqa: MOD-025
+class CheckoutInventoryException(BusinessLogicException):  # noqa: MOD025
     """Raised when inventory check fails during checkout."""
 
     def __init__(self, product_id: int, available: int, requested: int):