fix: column selector dropdown overflow for CSV datasets with many columns

[sahusiddharth]

resolves: #7942

Changes

• Added scrolling functionality to the ColumnMultiSelector dropdown
• Applied responsive max-height constraint (40vh) with vertical overflow scroll

Problem

When uploading CSV datasets with a large number of columns (10+), the column selector dropdown would overflow beyond the viewport, making it inconvenient to select columns that appeared below the fold.

Solution

Applied a max-height constraint using viewport-relative units (40% of viewport height) and vertical scrolling to the ListBox component

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Note

Constrain the ListBox in DatasetFromCSVForm column selector to 40vh with vertical scrolling to prevent dropdown overflow.

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[sahusiddharth]

Hi @axiomofjoy

whenever you get a chance, could you please take a look at this PR and let me know if any changes are needed?