Merge pull request #199 from wahajahmed010/fix/192-190-param-decorator-cors-docs

refactor: simplify param decorator lookup and document CORS pipeline step

Author: VikramAditya33

src/http/routing/route-registry.ts

@@ -449,6 +449,7 @@ export class RouteRegistry {
    * Execute a route handler with middleware pipeline
    *
    * Executes the full middleware pipeline:
+   * 0. CORS - Handle CORS headers and preflight
    * 1. Guards - Authorization checks
    * 2. Body parsing - Parse request body if present
    * 3. Pipes - Transform/validate body

src/websocket/decorators/param-decorator.utils.ts

@@ -71,9 +71,8 @@ export function createParamDecorator(
     ];
 
     // Check if this parameter index already has metadata
-    const existingIndex = existingParams.findIndex((p) => p.index === parameterIndex);
-    if (existingIndex !== -1) {
-      const existing = existingParams[existingIndex];
+    const existing = existingParams.find((p) => p.index === parameterIndex);
+    if (existing) {
       const existingDecoratorName = PARAM_TYPE_TO_DECORATOR_NAME[existing.type];
       throw new Error(
         `${decoratorName} decorator: parameter at index ${parameterIndex} already has @${existingDecoratorName} decorator applied. ` +