fix(twitter): confine uploadMedia paths to cwd

[SashaMIT]

Why

upload_media passes agent-controlled filePath straight to v1.uploadMedia with no cwd/realpath confine. A prompt-injected path (e.g. ../../.env, /etc/passwd) can read arbitrary process-readable files and exfiltrate them via Twitter media upload.

Same local-path class as flaunch #1424 / zora #1425, on the Twitter action provider.

Fix

resolveSafeLocalMediaPath: resolve under process.cwd(), require realpath stays under that root, then upload only the confined path.

Test plan

• npx jest src/action-providers/twitter/utils.test.ts src/action-providers/twitter/twitterActionProvider.test.ts (20/20)
• In-cwd relative path still uploads
• ../ and absolute outsides fail closed before uploadMedia

Made with Cursor

[cb-heimdall]

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