refactor: add mcp and skills to llmService

- Deleted the llmSkillsService implementation and its associated methods
for listing provider skills.
- Updated tests to use llmService instead of llmMcpService and
llmSkillsService for handling MCP and skills functionalities.
- Adjusted test cases to reflect the new service structure while
maintaining existing functionality.

server/src/modules/llm/providers/runtimes/codex-mcp.runtime.ts

@@ -0,0 +1,133 @@
+import os from 'node:os';
+import path from 'node:path';
+
+import { AppError } from '@/shared/utils/app-error.js';
+import type {
+  McpScope,
+  ProviderMcpServer,
+  UpsertProviderMcpServerInput,
+} from '@/modules/llm/providers/provider.interface.js';
+import { BaseProviderMcpRuntime } from '@/modules/llm/providers/runtimes/base-provider-mcp.runtime.js';
+import {
+  readObjectRecord,
+  readOptionalString,
+  readStringArray,
+  readStringRecord,
+  readTomlConfig,
+  writeTomlConfig,
+} from '@/modules/llm/providers/runtimes/mcp-runtime.utils.js';
+
+/**
+ * Codex MCP runtime backed by user/project `.codex/config.toml`.
+ */
+export class CodexMcpRuntime extends BaseProviderMcpRuntime {
+  constructor() {
+    super('codex', ['user', 'project'], ['stdio', 'http']);
+  }
+
+  /**
+   * Reads Codex MCP servers from user/project config.toml scopes.
+   */
+  protected async readScopedServers(scope: McpScope, workspacePath: string): Promise<Record<string, unknown>> {
+    const filePath = scope === 'user'
+      ? path.join(os.homedir(), '.codex', 'config.toml')
+      : path.join(workspacePath, '.codex', 'config.toml');
+    const config = await readTomlConfig(filePath);
+    return readObjectRecord(config.mcp_servers) ?? {};
+  }
+
+  /**
+   * Writes Codex MCP servers to user/project config.toml scopes.
+   */
+  protected async writeScopedServers(
+    scope: McpScope,
+    workspacePath: string,
+    servers: Record<string, unknown>,
+  ): Promise<void> {
+    const filePath = scope === 'user'
+      ? path.join(os.homedir(), '.codex', 'config.toml')
+      : path.join(workspacePath, '.codex', 'config.toml');
+    const config = await readTomlConfig(filePath);
+    config.mcp_servers = servers;
+    await writeTomlConfig(filePath, config);
+  }
+
+  /**
+   * Builds one Codex-native server object from the unified input payload.
+   */
+  protected buildServerConfig(input: UpsertProviderMcpServerInput): Record<string, unknown> {
+    if (input.transport === 'stdio') {
+      if (!input.command?.trim()) {
+        throw new AppError('command is required for stdio MCP servers.', {
+          code: 'MCP_COMMAND_REQUIRED',
+          statusCode: 400,
+        });
+      }
+
+      return {
+        command: input.command,
+        args: input.args ?? [],
+        env: input.env ?? {},
+        env_vars: input.envVars ?? [],
+        cwd: input.cwd,
+      };
+    }
+
+    if (!input.url?.trim()) {
+      throw new AppError('url is required for http MCP servers.', {
+        code: 'MCP_URL_REQUIRED',
+        statusCode: 400,
+      });
+    }
+
+    return {
+      url: input.url,
+      bearer_token_env_var: input.bearerTokenEnvVar,
+      http_headers: input.headers ?? {},
+      env_http_headers: input.envHttpHeaders ?? {},
+    };
+  }
+
+  /**
+   * Normalizes one Codex server object.
+   */
+  protected normalizeServerConfig(
+    scope: McpScope,
+    name: string,
+    rawConfig: unknown,
+  ): ProviderMcpServer | null {
+    if (!rawConfig || typeof rawConfig !== 'object') {
+      return null;
+    }
+
+    const config = rawConfig as Record<string, unknown>;
+    if (typeof config.command === 'string') {
+      return {
+        provider: 'codex',
+        name,
+        scope,
+        transport: 'stdio',
+        command: config.command,
+        args: readStringArray(config.args),
+        env: readStringRecord(config.env),
+        cwd: readOptionalString(config.cwd),
+        envVars: readStringArray(config.env_vars),
+      };
+    }
+
+    if (typeof config.url === 'string') {
+      return {
+        provider: 'codex',
+        name,
+        scope,
+        transport: 'http',
+        url: config.url,
+        headers: readStringRecord(config.http_headers),
+        bearerTokenEnvVar: readOptionalString(config.bearer_token_env_var),
+        envHttpHeaders: readStringRecord(config.env_http_headers),
+      };
+    }
+
+    return null;
+  }
+}