feat: add MCP servers to agent mode

- Update agent mode to use prepareMcpConfig instead of empty config
- Update prepareMcpConfig to accept both ParsedGitHubContext and AutomationContext
- Add type guards for context-specific properties (isPR, entityNumber)
- This enables bot actors to use full MCP capabilities via workflow_dispatch

src/mcp/install-mcp-server.ts

@@ -1,6 +1,6 @@
 import * as core from "@actions/core";
 import { GITHUB_API_URL, GITHUB_SERVER_URL } from "../github/api/config";
-import type { ParsedGitHubContext } from "../github/context";
+import type { GitHubContext } from "../github/context";
 import { Octokit } from "@octokit/rest";
 
 type PrepareConfigParams = {
@@ -12,7 +12,7 @@ type PrepareConfigParams = {
   additionalMcpConfig?: string;
   claudeCommentId?: string;
   allowedTools: string[];
-  context: ParsedGitHubContext;
+  context: GitHubContext;
 };
 
 async function checkActionsReadPermission(
@@ -115,7 +115,7 @@ export async function prepareMcpConfig(
     const hasActionsReadPermission =
       context.inputs.additionalPermissions.get("actions") === "read";
 
-    if (context.isPR && hasActionsReadPermission) {
+    if ('isPR' in context && context.isPR && hasActionsReadPermission) {
       // Verify the token actually has actions:read permission
       const actuallyHasPermission = await checkActionsReadPermission(
         process.env.ACTIONS_TOKEN || "",
@@ -141,7 +141,7 @@ export async function prepareMcpConfig(
           GITHUB_TOKEN: process.env.ACTIONS_TOKEN,
           REPO_OWNER: owner,
           REPO_NAME: repo,
-          PR_NUMBER: context.entityNumber?.toString() || "",
+          PR_NUMBER: 'entityNumber' in context ? context.entityNumber?.toString() || "" : "",
           RUNNER_TEMP: process.env.RUNNER_TEMP || "/tmp",
         },
       };