Allow multiparameter assigned attributes to be used with `text_field`

Between 4.2 and 5.0 the behavior of how multiparameter attributes
interact with `_before_type_cast` changed. In 4.2 it returns the
post-type-cast value. After 5.0, it returns the hash that gets sent to
the type. This behavior is correct, but will cause an issue if you then
tried to render that value in an input like `text_field` or
`hidden_field`.

In this case, we want those fields to use the post-type-cast form,
instead of the `_before_type_cast` (the main reason it uses
`_before_type_cast` at all is to avoid losing data when casting a
non-numeric string to integer).

I've opted to modify `came_from_user?` rather than introduce a new
method for this as I want to avoid complicating that contract further,
and technically the multiparameter hash didn't come from assignment, it
was constructed internally by AR.

Close #27888.

activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb

@@ -21,6 +21,10 @@ def initialize(defaults: {})
            end
          end

          define_method(:value_constructed_by_mass_assignment?) do |value|
            value.is_a?(Hash)
          end

          define_method(:value_from_multiparameter_assignment) do |values_hash|
            defaults.each do |k, v|
              values_hash[k] ||= v

activemodel/lib/active_model/type/value.rb

@@ -86,6 +86,10 @@ def changed_in_place?(raw_old_value, new_value)
        false
      end

      def value_constructed_by_mass_assignment?(_value) # :nodoc:
        false
      end

      def map(value) # :nodoc:
        yield value
      end

activerecord/CHANGELOG.md

@@ -1,3 +1,8 @@
*   Values constructed using multi-parameter assignment will now use the
    post-type-cast value for rendering in single-field form inputs.

    *Sean Griffin*

*   `Relation#joins` is no longer affected by the target model's
    `current_scope`, with the exception of `unscoped`.

activerecord/lib/active_record/attribute.rb

@@ -174,7 +174,7 @@ def type_cast(value)
        end

        def came_from_user?
          true
          !type.value_constructed_by_mass_assignment?(value_before_type_cast)
        end
      end

activerecord/test/cases/multiparameter_attributes_test.rb

@@ -383,4 +383,15 @@ def test_multiparameter_assignment_of_aggregation_with_large_index

    assert_equal("address", ex.errors[0].attribute)
  end

  def test_multiparameter_assigned_attributes_did_not_come_from_user
    topic = Topic.new(
      "written_on(1i)" => "1952",
      "written_on(2i)" => "3",
      "written_on(3i)" => "11",
      "written_on(4i)" => "13",
      "written_on(5i)" => "55",
    )
    refute_predicate topic, :written_on_came_from_user?
  end
end