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
