Add missing primitives to ra-core

[slax57]

Problem

The following primitives are either not exported, or not exported from ra-core:

• FilterContext types
• hooks savedQueries (WIP)
• genericMemo
• useSupportCreateSuggestions
• add empty in BaseFieldProps

Solution

For each:

• Move code
• Add stories
• Add tests
• Add documentation

How To Test

Describe the steps required to test the changes

Additional Checks

• The PR targets master for a bugfix or a documentation fix, or next for a feature
• The PR includes unit tests (if not possible, describe why)
• The PR includes one or several stories (if not possible, describe why)
• The documentation is up to date

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