[Idea] Support custom checks on TableDefinition methods

[cthomas-figma]

I'd like to propose adding general support for custom checks on TableDefinition methods ex. column or references

This was proposed in #170 as a mechanism to check for foreign key creations in TableDefinitions and was closed since creating foreign keys on an empty table is not a dangerous operaiton. My motivation for TableDefinition is different. I'd like to broadly restrict the schema that can be created via custom checks on TableDefinition. For example, at Figma we require folks to use bigint rather than integer columns to avoid overflow bugs. The below migration would not be allowed to run since it creates a new table with an integer column.

create_table(:photos) do |t|
  t.integer :like_count
  t.references :photographer, null: false, foreign_key: true, type: :uuid
end

Also full disclosure, I'm somewhat new to the ruby/rails ecosystem so please let me know if the "restrict the schema" problem would be better solved by a different tool.