[dajiaohuang]

Brief Information

This pull request is in the type of:

• bug fixing
• new feature
• others

What does this PR do?

Adds a focused visual regression case for vertical continuous visualMap handle-label overlap.

Fixed issues

• Follow-up coverage for [Bug] Continuous visualMap handle labels overlap when handles are very close #21766; the rendering fix is already present in current source via fix(visualMap): prevent tooltip label overlap #21586.

Details

Before: What was the problem?

The overlap fix covers the reported behavior, but the visual regression suite has no focused vertical case for handles that are very close or coincident.

After: How does it behave after the fixing?

A standalone synthetic-data fixture renders [49, 51] and [50, 50] ranges and is included in the primary visual-case list. The fixture contains no real-world or customer data.

Document Info

• This PR doesn't relate to document changes
• The document should be updated later
• The document changes have been made in apache/echarts-doc#xxx

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

test/visualMap-handle-label-overlap.html

Merging options

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

Other information

Checks run: JavaScript syntax checks for the new inline script and test/-cases.js, plus git diff --check. A synthetic SSR positive control against the checked-in dist/echarts.js 6.1.0 reproduced 8 px overlap for [49, 51] and 12 px for [50, 50]; that is the released bundle, not a build of current TypeScript source. The current-source build and Puppeteer visual suite were not run. The repository's CONTRIBUTING.md and PR template specify no mandatory test command for this test-only change; no current-source browser result is claimed. No CI was queried.

[echarts-bot]

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