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

This reverts commit cefe963a6b.

src/mcp/install-mcp-server.ts

@@ -100,7 +100,6 @@ export async function prepareMcpConfig(
           REPO_OWNER: owner,
           REPO_NAME: repo,
           BRANCH_NAME: branch,
-          BASE_BRANCH: process.env.BASE_BRANCH || "",
           REPO_DIR: process.env.GITHUB_WORKSPACE || process.cwd(),
           GITHUB_EVENT_NAME: process.env.GITHUB_EVENT_NAME || "",
           IS_PR: process.env.IS_PR || "false",