[RaphaelFakhri]

Summary

Fixes #829.

When a list item contains block children separated by whitespace, the HTML normalizer turns each whitespace run into its own empty list item. This is the shape CommonMark renderers produce for loose lists (<li>\n<p>a</p>\n</li>), and it is common in pretty-printed HTML. With useHtmlNormalizer enabled (the default), a two-item list gets four extra empty list items.

flush_li_buffer (C) and flushLiBuffer (web port) only skipped an empty buffer. They now also skip a whitespace-only buffer, the same check flush_inline_p already uses for inter-block whitespace. Intentionally empty <li></li> items are still emitted, as covered by EmptyListItems.

Impacts the HTML normalizer on iOS, Android (shared cpp/parser/GumboNormalizer.c) and web (src/web/normalization/htmlNormalizer.ts).

Test Plan

• cd cpp && cmake -B build && cmake --build build && ctest --test-dir build: InterBlockWhitespace has two new cases. Without the fix it fails with <ul><li>\n</li><li>a</li><li>\n</li><li>\n</li><li>b</li><li>\n</li></ul>; with the fix all 15 tests pass.
• yarn jest --selectProjects web src/web/__tests__/htmlNormalizer.test.ts: the same two cases fail without the fix (2 failed, 425 passed) and pass with it (427 passed).

Screenshots / Videos

Not applicable. The change is covered by the normalizer unit tests.

Compatibility

OS	Implemented
iOS	✅
Android	✅
Web	✅

Checklist

• E2E tests are passing
• Required E2E tests have been added (if applicable)

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🟢 Approval recommended

The focused changes are consistent across platforms, have matching regression coverage, and leave no unresolved review findings.

No open issues 🎉

_{Review effort: Balanced}