Include tags in `dbt_columns` table

[Bley5271]

Is your feature request related to a problem? Please describe. We utilize column tags to indicate primary keys in the staging and transformation layers. I can find these tags in dbt_tests since they're attached to a column with a uniqueness test. However, when a model's uniqueness is based on a unique combination of columns, the test lives at the model level so the tag doesn't come through in the dbt_tests table.

Describe the solution you'd like I would like dbt_columns to contain a field for column tags.

Describe alternatives you've considered We can utilize Snowflake's information_schema for public layer primary keys but tags at the lower levels are far less official in Snowflake's eyes.

Additional context

Would you be willing to contribute this feature? If my knowledge is sufficient, I would be happy to help where I can!