fix: Shared Tooltip part of series invisible

[ZahidChandio]

New Pull Request

isInitialSeriesSameLen returns false due to hidden series having 0-length data ininitialSeries. This forces the tooltip to be treated as non-shared, and due toisXNumericusage in categorical charts, it falls back to displaying the first series info.

Fixes #5140

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• My branch is up to date with any changes from the main branch

Tooltip display after the fix

Screen.Recording.2025-12-18.at.7.50.56.PM.mov

[Copilot]

Pull request overview

This PR fixes a bug where shared tooltips display incorrect data when some series are hidden/collapsed. The issue occurred because isInitialSeriesSameLen() incorrectly returned false when hidden series had zero-length data, causing the tooltip to fall back to displaying only the first series.

Key Changes:

• Modified isInitialSeriesSameLen() to filter out collapsed series before checking data length consistency
• Removed an unnecessary blank line

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[junedchhipa]

@ZahidChandio Please consider the changes suggested by CoPilot in above comments

[ZahidChandio]

Code updated @junedchhipa.

[junedchhipa]

Looks good to me.