(core) Formula UI redesign

Summary:
Redesigning column type section to make it more user-friendly. Introducing column behavior concept.
Column can be either:
- Empty Formula Column: initial state (user can convert to Formula/Data Column)
- Data Column: non formula column with or without trigger (with option to add trigger, or convert to formula)
- Formula Column: pure formula column, with an option to convert to data column with a trigger.

Test Plan: Existing tests.

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D3092

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