refactor: Address code review feedback

- Replace 'as any' with proper FeaturesConfig type definition
- Improve CHECK constraint SQL injection validation with comprehensive patterns
- Move isValidIdentifier to shared validation module
- Add comprehensive unit tests for identifier validation (12 tests)
- Fix all linting issues
- All 52 unit tests passing

Co-authored-by: johndoe6345789 <224850594+johndoe6345789@users.noreply.github.com>

src/utils/featureConfig.ts

@@ -40,31 +40,41 @@ export type ConstraintType = {
   requiresExpression: boolean;
 };
 
+// Type definition for the features config structure
+type FeaturesConfig = {
+  features: Feature[];
+  dataTypes: DataType[];
+  constraintTypes?: ConstraintType[];
+  navItems: NavItem[];
+};
+
+const config = featuresConfig as FeaturesConfig;
+
 export function getFeatures(): Feature[] {
-  return featuresConfig.features.filter(f => f.enabled);
+  return config.features.filter(f => f.enabled);
 }
 
 export function getFeatureById(id: string): Feature | undefined {
-  return featuresConfig.features.find(f => f.id === id && f.enabled);
+  return config.features.find(f => f.id === id && f.enabled);
 }
 
 export function getDataTypes(): DataType[] {
-  return featuresConfig.dataTypes;
+  return config.dataTypes;
 }
 
 export function getConstraintTypes(): ConstraintType[] {
-  return (featuresConfig as any).constraintTypes || [];
+  return config.constraintTypes || [];
 }
 
 export function getNavItems(): NavItem[] {
-  return featuresConfig.navItems.filter((item) => {
+  return config.navItems.filter((item) => {
     const feature = getFeatureById(item.featureId);
     return feature && feature.enabled;
   });
 }
 
 export function getEnabledFeaturesByPriority(priority: string): Feature[] {
-  return featuresConfig.features.filter(
+  return config.features.filter(
     f => f.enabled && f.priority === priority,
   );
 }