refactor(auth): remove keys auth module and align tests

- remove server auth module and client keys page/routes/api to simplify flow

- update mcp and scenario tests to match uuid routes and step schema

server/test/mcp.controller.spec.ts

@@ -69,14 +69,14 @@ describe("McpController", () => {
     });
   });
 
-  // ── list_keys tool ─────────────────────────────────────────────────────────
+  // ── list_keys tool (removed) ──────────────────────────────────────────────
 
   describe("list_keys", () => {
-    it("returns a result with text content containing a JSON array", async () => {
+    it("returns MCP error for removed tool", async () => {
       const { status, rpc } = await mcpCall("list_keys");
       expect(status).toBe(200);
-      const result = rpc.result as { content: { text: string }[] };
-      expect(Array.isArray(JSON.parse(result.content[0].text))).toBe(true);
+      const result = rpc.result as { isError: boolean; content?: { text: string }[] };
+      expect(result.isError).toBe(true);
     });
   });