- docx-table-ops: apply MIN/MAX_COLUMN_WIDTH clamping in the empty-table
branch so tables with 15+ columns don't produce sub-50 widths that Feishu
rejects as invalid column_width values.
- docx.ts (data URI branch): validate the ';base64' marker before decoding
so plain/URL-encoded data URIs are rejected with a clear error; also validate
the payload against the base64 alphabet (same guard already applied in the
plain-base64 branch) so malformed inputs fail fast rather than producing
opaque downstream Feishu errors.
a3aeeb9f20