🧪 test: add coverage for setNested in generate-manifest.js

[akutuva21]

🎯 What: The setNested utility function within scripts/generate-manifest.js lacked unit test coverage, creating a potential blind spot for prototype pollution vulnerabilities and basic logical errors during property assignment.

📊 Coverage:

• Basic nested property assignment
• Overwriting non-object values (strings, arrays)
• Preserving existing properties in the path
• Comprehensive prevention of prototype pollution vectors (__proto__, constructor, prototype)

✨ Result: Enhanced test coverage guarantees robust property assignment logic and secures the metadata manifest generation process against prototype pollution.

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PR created automatically by Jules for task 11384957934573668602 started by @akutuva21

[google-labs-jules]

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[akutuva21]

pull the latest code and resolve merge conflicts

[google-labs-jules]

pull the latest code and resolve merge conflicts

I have pulled the latest code from main, resolved the merge conflicts in scripts/generate-manifest.js and scripts/generate-manifest.test.js, and re-added the test coverage for setNested. The test suite now passes successfully.