feat(time): parse ISO week strings. close #21578

[ecoyoung]

Brief Information

Prepared with Codex and approved for submission by @ecoyoung.

• bug fixing
• new feature
• others

What does this PR do?

Parse YYYY-Www as Monday of the ISO week at local midnight, matching existing date inputs without a timezone.

Fixed issues

Closes #21578.

Details

Before: What was the problem?

Values such as 2026-W04 produce invalid dates on a time axis.

After: How does it behave after the fixing?

2026-W04 resolves to January 19, 2026. Cross-year weeks are supported; invalid week numbers, including week 53 in a 52-week year, are rejected. This adds no dependency and does not add week-day/time parsing or week-label formatting.

Document Info

• This PR doesn't relate to document changes
• The document should be updated later
• The document changes have been made in docs(time): document ISO week inputs echarts-doc#535

English and Chinese docs are in apache/echarts-doc#535 (draft pending the release target).

Misc

Security Checking

• This PR uses security-sensitive Web APIs.

ZRender Changes

• This PR depends on ZRender changes (ecomfe/zrender#xxx).

Related test cases or examples to use the new APIs

198 unit tests pass, including parsing and dataZoom coverage. The affected suites also pass in New York and Berlin timezones. Typecheck, lint, and header checks pass.

Merging options

• Please squash the commits into a single one when merging.

Other information

The new parsing tests fail before this change.

[echarts-bot]

Thanks for your contribution!
The community will review it ASAP. In the meanwhile, please checkout the coding standard and Wiki about How to make a pull request.

Please DO NOT commit the files in dist, i18n, and ssr/client/dist folders in a non-release pull request. These folders are for release use only.

Document changes are required in this PR. Please also make a PR to apache/echarts-doc for document changes and update the issue id in the PR description. When the doc PR is merged, the maintainers will remove the PR: awaiting doc label.