refactor(webhook): extract async context detach into a helper

pkg/modules/webhook/middleware.go

@@ -314,27 +314,7 @@ func webhookMiddleware(w *Webhook) api.Middleware {
 						return c.NoContent(http.StatusNoContent)
 					}
 
-					if deadline, ok := ctx.Deadline(); ok {
-						// Create a new context derived from Background (detached from Request)
-						// but with the same deadline as the original context.
-						detachedCtx, detachedCancel := context.WithDeadline(context.Background(), deadline)
-
-						// Replace the embedded context in the api.Context struct.
-						// The modules downstream will now use this detached context.
-						ctx.Context = detachedCtx
-
-						// We must wrap the cancel function.
-						// 1. detachedCancel() cleans up our new detached context.
-						// 2. originalCancel() (captured from c.Get("cancel")) cleans up the working directory.
-						originalCancel := cancel
-						cancel = func() {
-							detachedCancel()
-							originalCancel()
-						}
-					} else {
-						// Fallback if no deadline was set (rare, as newContext enforces it).
-						ctx.Context = context.Background()
-					}
+					cancel = detachAsyncContext(ctx, cancel)
 
 					// As a webhook URL has been given, we handle the request in a
 					// goroutine and return immediately.