add label option

[QWYNG]

Thank you for great gem!
This is a proposal and pull request at once.

Summary

Added option to display labels in ActiveRecord::Bitemporal::Visualizer

Sample code

# frozen_string_literal: true

require 'bundler/inline'

gemfile(true) do
  source 'https://rubygems.org'

  git_source(:github) { |repo| "https://github.com/#{repo}.git" }

  gem 'rails', '7.0.1'
  gem 'activerecord-bitemporal', path: '../activerecord-bitemporal'
  gem 'sqlite3'
  gem 'timecop'
end

require 'active_record'
require 'active_support/all'
require 'activerecord-bitemporal'

ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:')

ActiveRecord::Schema.define do
  create_table :companies, force: true do |t|
    t.integer :bitemporal_id

    t.string :name

    t.datetime :valid_from, precision: 6
    t.datetime :valid_to, precision: 6
    t.datetime :deleted_at, precision: 6
    t.datetime :transaction_from, precision: 6
    t.datetime :transaction_to, precision: 6

    t.timestamps
  end
end

Time.zone = 'UTC'

class Company < ActiveRecord::Base
  include ActiveRecord::Bitemporal
end

company = nil
Timecop.freeze('2023-02-28') do
  ActiveRecord::Bitemporal.valid_at('2000/01/01') do
    company = Company.create!(name: 'A')
  end
end

Timecop.freeze('2023-03-1') do
  ActiveRecord::Bitemporal.valid_at('2020/07/01') do
    company.reload.update!(name: 'C')
  end
end

puts ActiveRecord::Bitemporal::Visualizer.visualize(company, label: true)

output

 > ruby test.rb
Fetching gem metadata from https://rubygems.org/...........
~~ snip ~~
transaction_datetime    | valid_datetime
                        | 2000-01-01 00:00:00.000
                        |                   | 2020-07-01 00:00:00.000
                        |                   |                   | 9999-12-31 00:00:00.000
2023-02-28 00:00:00.000 +---------------------------------------+
                        |                                       |
                        |                                       |
                        |                                       |
                        |                                       |
2023-03-01 00:00:00.000 +-------------------+-------------------+
                        |                   |*******************|
                        |                   |*******************|
                        |                   |*******************|
                        |                   |*******************|
9999-12-31 00:00:00.000 +-------------------+-------------------+

[osyo-manga]

@QWYNG Thanks! Great!
I think it would be better if it is output by default rather than optional, since it does not affect the functionality and it would be preferable to have it by default.

[QWYNG]

@osyo-manga
thank you!
Changed to output labels by default

[osyo-manga]

@QWYNG OK, Thanks!