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/src/mcp/mcp.service.ts

@@ -3,7 +3,6 @@ import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
 import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
 import { z } from "zod";
 import type { Request, Response } from "express";
-import { AuthService } from "../auth/auth.service";
 import { SessionService } from "../session/session.service";
 import { SessionContextService } from "../session/session-context.service";
 import { EnvironmentService } from "../environment/environment.service";
@@ -17,7 +16,6 @@ import pkg from "../../package.json";
 @Injectable()
 export class McpService {
   constructor(
-    private readonly authService: AuthService,
     private readonly sessionService: SessionService,
     private readonly sessionContextService: SessionContextService,
     private readonly environmentService: EnvironmentService,
@@ -33,53 +31,6 @@ export class McpService {
   }
 
   private registerTools(server: McpServer): void {
-    // ── Auth ──────────────────────────────────────────────────────────────────
-
-    server.registerTool(
-      "list_keys",
-      { description: "List available key identifiers from the keys directory" },
-      async () => {
-        const keys = this.authService.listKeys();
-        return {
-          content: [{ type: "text" as const, text: JSON.stringify(keys) }],
-        };
-      },
-    );
-
-    server.registerTool(
-      "login",
-      {
-        description:
-          "Log in using a file key against a named environment and store the session",
-        inputSchema: {
-          key: z
-            .string()
-            .describe(
-              "Key identifier (filename without extension from keys/ dir)",
-            ),
-          environmentName: z
-            .string()
-            .describe("Environment name to resolve login/cabinet URLs"),
-          sessionName: z
-            .string()
-            .optional()
-            .describe(
-              "Session name to store credentials under. Auto-UUID if omitted.",
-            ),
-        },
-      },
-      async ({ key, environmentName, sessionName }) => {
-        const result = await this.authService.login(
-          key,
-          environmentName,
-          sessionName,
-        );
-        return {
-          content: [{ type: "text" as const, text: JSON.stringify(result) }],
-        };
-      },
-    );
-
     // ── Sessions ──────────────────────────────────────────────────────────────
 
     server.registerTool(