Add an improved Multi Select Filter component to history page filters

[adhityamamallan]

Summary

• Create new MultiSelectFilter component with overridden selection menu, with checkboxes and Select All
• Use component in History Page filters (type & status)
• (misc) Fix styling in Page Filters so that non-minified filters share space evenly regardless of content
• (misc) Delete unused styles from page-filters.styles.ts

Test plan

Added unit tests + ran locally.

Filter in action

Unmodified filter

Modified filter

Empty filter

[Copilot]

Pull Request Overview

This PR adds an improved MultiSelectFilter component with checkboxes and "Select All" functionality to replace the existing multi-select dropdowns on the workflow history page filters.

• Creates a new MultiSelectFilter component with overridden dropdown menu containing checkboxes and Select All option
• Replaces existing Select components in Type and Status filters with the new MultiSelectFilter
• Improves filter layout styling for consistent spacing across non-minified filters

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
workflow-history-filters-type.tsx	Replaces BaseUI Select with new MultiSelectFilter component
workflow-history-filters-status.tsx	Replaces BaseUI Select with new MultiSelectFilter component
workflow-history-filters-type.styles.ts	Removes unused styling file
workflow-history-filters-status.styles.ts	Removes unused styling file
page-filters.styles.ts	Removes unused overrides and styling code
page-filters-fields.styles.ts	Improves filter layout styling for consistent spacing
multi-select-filter/*	Adds new MultiSelectFilter component with custom dropdown menu

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