Fix: html-wasm export prompted an overwrite

[swapnilbehere]

📝 Summary

Fixes #6012

🔍 Description of Changes

The issue prompted an index.html overwrite whenever an index file is not provided. This lead to a bug where export_assests() exported everything including index.html, which was then overwritten by watch_and_export() to store the actual content.

My fix:
The flag "ignore_index_html" should always be true when exporting as html-wasm.

📋 Checklist

• I have read the contributor guidelines.
• For large changes, or changes that affect the public API: this change was discussed or approved through an issue, on Discord, or the community discussions (Please provide a link if applicable).
• I have added tests for the changes made.
• I have run the code and verified that it works as expected.

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Project	Deployment	Preview	Comments	Updated (UTC)
marimo-docs	Ready	Preview	Comment	Nov 3, 2025 11:40pm

[github-actions]

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[swapnilbehere]

I have read the CLA Document and I hereby sign the CLA

[dmadisetti]

Hmm, I don't think this is totally correct- but running the tests to see what fails. Thank you though!