fix(signup): create proper index.tsx for signup folder, rename job-seeker to jobseeker

- Fix routing structure with index.tsx
- Remove conflicting signup.tsx at root level
- Rename job-seeker.tsx to jobseeker.tsx for cleaner URLs

src/routes/signup/index.tsx

@@ -2,16 +2,16 @@ import { useNavigate, useSearchParams } from "@solidjs/router";
 import { createEffect } from "solid-js";
 
 /**
- * Legacy signup route - redirects to role-specific signup pages
+ * Signup index route - redirects to role-specific signup pages
  * 
- * This maintains backwards compatibility with old links:
+ * Routes:
+ * - /signup → /signup/job-seeker
  * - /signup?intent=company → /signup/company
  * - /signup?intent=job_seeker → /signup/job-seeker
  * - /signup?intent=professional → /signup/professional
  * - /signup?intent=customer → /signup/customer
- * - /signup (no intent) → /signup/job-seeker (default)
  */
-export default function SignupRedirectRoute() {
+export default function SignupIndexRoute() {
   const navigate = useNavigate();
   const [search] = useSearchParams();
 
@@ -40,7 +40,7 @@ export default function SignupRedirectRoute() {
       height: "100vh",
       background: "#07051a"
     }}>
-      <p style={{ color: "#fff" }}>Redirecting..."</p>
+      <p style={{ color: "#fff" }}>Redirecting...</p>
     </div>
   );
 }