Refactor tree filtering in CMSMain/HierarchyModelAdmin

[GuySartorelli]

Form fields for filtering in CMSMain are hardcoded - and some of the functionality is duplicated or else needlessly different between this filter functionality and GridFieldFilterHeader.

Relevant

• SPIKE Analyse how LeftAndMain and CMSMain are put together and how they could work better #2933
• original POC PR - this PR includes many additional notes and implementation details

Acceptance Criteria

• The fields to use for filtering are pulled from the model in the same way GridFieldFilterHeader does (i.e. it uses searchableFields())
• SearchContext is used for filtering in CMSMain the same way it is in GridFieldFilterHeader
• Any CMSSiteTreeFilter logic is either made generic if possible, or else used by the SearchContext for SiteTree wherever filtering pages is used
  • i.e. filtering pages in a gridfield uses the same logic as filtering pages in CMSMain
• A shared template and shared javascript/css are used for the filter in GridFieldFilter and CMSMain (with the ability to use different custom templates as desired - e.g. by trying to get specific templates by class name first, and falling back to the shared one)
• As much as feasible, PHP logic for filtering in GridFieldFilterHeader and CMSMain is shared

PRs

Enable WithinRangeFilter in searchable_fields

This set of PRs is required to match the ranged filtering against LastEdited which is currently only possible for SiteTree inside CMSMain.

• FIX Handle composite fields in GridFIeldFilterHeader silverstripe-framework#11609 (Reassign to Guy after merging this one)
• NEW Handle WithinRangeFilter in searchable_fields and SearchContext silverstripe-framework#11602
• DOC Document new filter by range functionality developer-docs#687

Avoid filterByCallback() in CMSSiteTreeFilter subclasses

Important

Reassign to Guy if the above are merged but the below sink CI hasn't gone green yet

This set of PRs is required to migrate the SiteTree filtering functionality to primarily use SearchContext, which requires filtering be done by the ORM not in PHP.

Kitchen sink CI run

• NEW Add new methods for querying data in various version modes silverstripe-versioned#489
• ENH Don't use filterByCallback() in CMSSiteTreeFilter classes #3057
• ENH Take advantage of new functionality in Versioned silverstripe-versioned-admin#388
• DOC Document new versioned methods developer-docs#690

The main refactoring

The above should be merged before reviewing these, as some of the code from the above PRs is also included in the below.

• API Refactor SiteTree filtering to work like GridField filters #3052
• Various changes to support refactoring CMS search filter functionality silverstripe-framework#11587
• API Various changes silverstripe-admin#1897