Allow column-level permissions to be defined at the managed template level

Description

Problem
Managed templates doesn’t appear to support defining column-level permissions at the managed template level. The column permissions must be configured on each individual board after creation.

In practice, this creates significant manual overhead and increases risk of inconsistency.

Impact
In one real use case:

  • 8 boards are created from a single managed template
  • Each board has 15 columns that require restrictions
  • This resulted in 120 manual column permission updates

What are you trying to achieve

Add support for defining and enforcing column-level permissions directly within managed templates, including:

  • Ability to lock column permissions at the managed template level
  • Automatic inheritance of column restrictions when boards are created from the template OR the template is updated later to sync existing boards using it.