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The sync_marketplace_to_plugins.py hook script resolves the source field from marketplace.json into a file path but does not verify that the resolved path stays within the expected plugin root. A tampered marketplace.json could write files outside the repository. This PR adds a guard that skips any entry whose resolved path escapes the marketplace root.

• Added a check after plugin_dir = (marketplace_dir / source).resolve() that compares the resolved path against the marketplace root
• If the resolved path escapes the root, the entry is skipped with a warning to stderr and the loop continues