Fix: Pass correct branch names to MCP file ops server (#279)

* Reapply "feat: defer remote branch creation until first commit (#244)" (#278)

This reverts commit 018533dc9a.

* fix branch names

src/entrypoints/prepare.ts

@@ -12,7 +12,6 @@ import { checkHumanActor } from "../github/validation/actor";
 import { checkWritePermissions } from "../github/validation/permissions";
 import { createInitialComment } from "../github/operations/comments/create-initial";
 import { setupBranch } from "../github/operations/branch";
-import { updateTrackingComment } from "../github/operations/comments/update-with-branch";
 import { configureGitAuth } from "../github/operations/git-config";
 import { prepareMcpConfig } from "../mcp/install-mcp-server";
 import { createPrompt } from "../create-prompt";
@@ -67,17 +66,7 @@ async function run() {
     // Step 8: Setup branch
     const branchInfo = await setupBranch(octokit, githubData, context);
 
-    // Step 9: Update initial comment with branch link (only for issues that created a new branch)
-    if (branchInfo.claudeBranch) {
-      await updateTrackingComment(
-        octokit,
-        context,
-        commentId,
-        branchInfo.claudeBranch,
-      );
-    }
-
-    // Step 10: Configure git authentication if not using commit signing
+    // Step 9: Configure git authentication if not using commit signing
     if (!context.inputs.useCommitSigning) {
       try {
         await configureGitAuth(githubToken, context, commentData.user);
@@ -87,7 +76,7 @@ async function run() {
       }
     }
 
-    // Step 11: Create prompt file
+    // Step 10: Create prompt file
     await createPrompt(
       commentId,
       branchInfo.baseBranch,
@@ -96,13 +85,14 @@ async function run() {
       context,
     );
 
-    // Step 12: Get MCP configuration
+    // Step 11: Get MCP configuration
     const additionalMcpConfig = process.env.MCP_CONFIG || "";
     const mcpConfig = await prepareMcpConfig({
       githubToken,
       owner: context.repository.owner,
       repo: context.repository.repo,
-      branch: branchInfo.currentBranch,
+      branch: branchInfo.claudeBranch || branchInfo.currentBranch,
+      baseBranch: branchInfo.baseBranch,
       additionalMcpConfig,
       claudeCommentId: commentId.toString(),
       allowedTools: context.inputs.allowedTools,