fix: avoid shell interpolation of user-supplied paths in deployment (command injection)

[yogikortisa]

Summary

prepareSourceDirectory() (lib/deployment/source-processor.js) and runUniversalMaker() (lib/deployment/universal-maker.js) build shell commands by string-interpolating user-controlled filesystem paths and run them via child_process.exec, which executes the string through /bin/sh -c.

The folderPath argument of the deploy_local_folder tool flows unsanitized into these commands (files: [folderPath] → prepareSourceDirectory → exec(`cp -R "${file}/." "${tempDir}/"`)). A path containing shell metacharacters therefore results in OS command execution on the host running the MCP server.

Fix

• source-processor.js: replace the cp -R shell call with fs.promises.cp(file, tempDir, { recursive: true }) — no subprocess, no shell. Removed the now-unused exec/util imports.
• universal-maker.js: replace the interpolated exec command with execFile(binPath, [...]) — argv array, no shell.

Both changes are behavior-preserving and remove the shell entirely from these code paths, eliminating the command-injection vector.

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[gemini-code-assist]

Code Review

This pull request addresses potential OS command injection vulnerabilities by replacing shell-based command executions with safer alternatives. In lib/deployment/source-processor.js, the shell command cp -R is replaced with fsp.cp, and in lib/deployment/universal-maker.js, exec is replaced with execFile to run the binary with an arguments array. Feedback on these changes suggests adding dereference: true to the fsp.cp options to ensure symlinks are dereferenced and do not become broken in the deployed container environment.

[yogikortisa]

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