Skip zero-size spreadsheet cells in renderTile. On sheets past the
8,000,000 px scroll cap, a cell clipped to nothing at the spacer's edge
(or a visible row or column the worker clamped to 0 px) was still created,
and the cell padding and border drew it as a 5 px box below the spacer
that grew the scroll area. The size is now computed before the element is
created and such cells are skipped, the same way the heading loops already
skip 0 px rows and columns. spreadsheet-preview.js is not an input of
SPREADSHEET_ASSET_VERSION, so the asset token stays valid.
Add zh-CN entries for the static spreadsheet preview strings (loading,
too large, no visible worksheets, empty worksheet, the warnings label,
timeout, failure, the four parser start and message failures, and the
unavailable message from panels-ui). The file-preview body is not a
skipped surface, so the exact-match entries apply with no code change.
The worker's admission refusal messages and the dynamic status message
stay English for a follow-up.
docs/security-architecture.md described the attachment gate as a
6-extension allowlist; it now names SUPPORTED_ATTACHMENT_EXTENSIONS in
src/attachment-registry.ts and what it covers, including the xlsx this
PR adds.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Codeman maintainer
34f211538a