[calcite-filter] Add support for custom filter function

[jcfranco]

Description

There is a need to support custom filtering for end-users (see #2208, #2209).

Acceptance Criteria

Allow users to pass a custom filter function to calcite-filter. This still needs more details, but a few items to consider:

• custom filter function should support pick/value list filtering
• could support async methods to allow for complex setups (need to gauge need for this)
• Enhancement: Provide additional filter options for calcite-value-list #2209 (comment) could be used as a base for the method
• Consider filtering in components (e.g., list via [List / List items] Support custom filtering supporting a filter function with a prop #6544)

cc @ffaubry, @dhrumil83, @AdelheidF, @benelan for additional requirement gathering

Relevant Info

Which Component

calcite-filter

Example Use Case

See linked issues from description.

[geospatialem]

@ffaubry @AdelheidF Calcite is considering this effort for a future milestone, and wanted to get your expertise with current and future workflows to help determine prioritization and need. Could you both speak to the impact and what you would expect CC would support?

[ffaubry]

We would like to have two features:

• a way to say what property of the list item we would like to filter on: label or description or both
• pass a function that would be invoked for each list item with the filter value and the list item itself

@geospatialem is it what you are looking for?

[AdelheidF]

I think the discussion in the issue that Dhrumil submitted is still valid. We still would like to add a second filter, e.g. field type, to a list with a text filter. See #2209 (comment).

[geospatialem]

Thank you both, that helps us with prioritization. Will be assigning to a future milestone in the next few weeks.