refactor: rename helmet middleware import and instance

- Updated the import statement to rename `helmetMiddleware` to `helmetFactory`.
- Adjusted the middleware instantiation accordingly for clarity and consistency.

Author: csikb

src/middleware/helmet.test.ts

@@ -51,9 +51,9 @@ describe('helmet', () => {
     const mockHelmet = vi.mocked(helmet)
     mockHelmet.mockReturnValue(mockExpressHelmet)
 
-    const { default: helmetMiddleware } = await import('./helmet.js')
+    const { default: helmetFactory } = await import('./helmet.js')
 
-    const middleware = helmetMiddleware()
+    const middleware = helmetFactory()
 
     const ctx = {
       req: {},
@@ -81,9 +81,9 @@ describe('helmet', () => {
     const mockHelmet = vi.mocked(helmet)
     mockHelmet.mockReturnValue(mockExpressHelmet)
 
-    const { default: helmetMiddleware } = await import('./helmet.js')
+    const { default: helmetFactory } = await import('./helmet.js')
 
-    const middleware = helmetMiddleware()
+    const middleware = helmetFactory()
 
     const ctx = {
       req: {},