Add user authentication and dynamic feature/category inputs

Implement Keycloak authentication, protected routes, and add combobox and autocomplete components for tool categories and features.

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artifacts/api-server/src/middleware/auth.ts

@@ -0,0 +1,9 @@
+import { type Request, type Response, type NextFunction } from "express";
+
+export function requireAuth(req: Request, res: Response, next: NextFunction): void {
+  if (!req.session.user) {
+    res.status(401).json({ error: "Authentication required" });
+    return;
+  }
+  next();
+}