refactor(backend): ♻️ extract sw middleware to redure main middleware complexity

routes/_middleware.ts

@@ -1,6 +1,7 @@
 import { FreshContext } from '$fresh/server.ts'
 import { useCsp } from ':src/csp/middleware.ts'
 import { useSecurityHeaders } from ':src/security_headers/middleware.ts'
+import { useServiceworker } from ':src/serviceworker/middleware.ts'
 import { useSession } from ':src/session/middleware.ts'
 import { SessionStore } from ':src/session/mod.ts'
 
@@ -15,11 +16,7 @@ export async function handler(request: Request, ctx: FreshContext) {
 	useSecurityHeaders(request, response, ctx)
 	await useCsp(request, response, ctx)
 	useSession(request, response, ctx)
-
+	useServiceworker(request, response, ctx)	
-	// Allow service worker to serve root scope
-	if (ctx.url.pathname.endsWith('island-startserviceworker.js')) {
-		response.headers.set('Service-Worker-Allowed', '/')
-	}
 
 	return response
 }

src/serviceworker/middleware.ts

@@ -0,0 +1,12 @@
+import { FreshContext } from '$fresh/server.ts'
+
+export function useServiceworker(
+    _request: Request,
+    response: Response,
+    ctx: FreshContext,
+) {
+    // Allow service worker to serve root scope
+    if (ctx.url.pathname.endsWith('island-startserviceworker.js')) {
+        response.headers.set('Service-Worker-Allowed', '/')
+    }
+}