[Sistent] Add UniversalFilter component to the sistent components page

Current Behavior

Layer5 and its projects use the Sistent library to enable component reuse across various projects.
The UniversalFilter is one of the core filtering components available in Sistent, but it is currently not represented in the centralized Sistent component documentation at https://layer5.io/projects/sistent/components.
Adding documentation for UniversalFilter will provide a clear reference for its usage, guidelines, and examples, helping developers understand and reuse the component consistently across Layer5 projects.

Desired Behavior

Add proper documentation for the UniversalFilter component, following the same structure used by other documented Sistent components.
The documentation should follow the new Sistent MDX documentation structure by creating the following files under:
src/collections/sistent/components/universal-filter/

• index.mdx: Overview of the UniversalFilter component for multi-attribute filtering across tables and catalogs.
• guidance.mdx: Filter schemas, date-range picker integrations, quick date options, and active filters handling.
• code.mdx: Code examples demonstrating multi-select column filtering, search inputs, and date pickers using <ThemeWrapper> and <CodeBlock>.

The completed documentation should be available on the Sistent components page and provide a centralized reference for developers using UniversalFilter.

Environment:

• Host OS:
• Browser:

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Start with src/custom/UniversalFilter.tsx and compare the existing component documentation structure under src/collections/sistent/components/. Create index.mdx, guidance.mdx, and code.mdx under src/collections/sistent/components/universal-filter/, then verify the UniversalFilter documentation appears on the Sistent components page.