`return` at the top level of a <script type="module"> is a SyntaxError
in strict mode, so the entire Three.js chart script was killed before
executing regardless of whether prices were available.
Replaced `if (total <= 0) return` with `if (total > 0) { ... }` wrapping
the full chart body. Also filter out holdings with value=0 before building
the arc geometry so a single un-priced ISIN can't produce a zero-arc slice.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>