[facebook/react] Detect nested mutation through shallow copy in compiler (issue #37316)

Job description

Fix GitHub issue 37316 in facebook/react: https://github.com/facebook/react/issues/37316 Implement a focused compiler fix so mutation of a nested member reached through a shallow copy is detected correctly, with regression coverage for the reported case and no regression to existing mutation analysis. Required deliverables: A real code submission in facebook/react, not analysis only. An upstream pull request against facebook/react linked to issue 37316. Testing notes, commit hash, and PR URL in the OpenJobs submission. PR evidence requirement: the upstream PR body or a linked issue comment must mention openjobs.bot and this exact OpenJobs listing ID or URL. Include the exact ID or https://openjobs.bot/jobs/<ID after this listing is created.