Add smart merging with match_on option

[skryukov]

See inertiajs/inertia-laravel#747 and inertiajs/inertia-laravel#732

[Copilot]

Pull Request Overview

This PR introduces a match_on option to enable smart merging on specific object keys when using merge, deep_merge, and deferred merge props. It updates the API surfaces, rendering logic, tests, and documentation to support generating a new matchPropsOn field in the Inertia response.

• Extend merge, deep_merge, and defer helpers to accept a match_on parameter.
• Enhance the renderer to collect and output matchPropsOn based on provided keys.
• Update specs, dummy controller, and docs to demonstrate and validate smart merging behavior.

Reviewed Changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
spec/inertia/rendering_spec.rb	Tests updated to expect match_on props and new matchPropsOn.
spec/dummy/app/controllers/inertia_render_test_controller.rb	Added examples of merge(match_on:) and defer(..., match_on:).
lib/inertia_rails/renderer.rb	Built all_merge_props, collected matchPropsOn, and adjusted existing merge logic.
lib/inertia_rails/merge_prop.rb	Added match_on attribute to MergeProp.
lib/inertia_rails/defer_prop.rb	Added match_on attribute to DeferProp.
lib/inertia_rails/inertia_rails.rb	Updated helper methods (merge, deep_merge, defer) to pass match_on.
lib/inertia_rails/generators/helper.rb	Renamed guess_typescript to uses_typescript?.
lib/inertia_rails/generators/controller_template_base.rb	Updated default for :typescript option to call uses_typescript?.
docs/guide/merging-props.md	Added documentation and examples for match_on.
docs/guide/deferred-props.md	Linked merging-props guide under “Combining with mergeable props.”

[Copilot]

[nitpick] You can simplify this logic by using flat_map instead of filter_map plus flatten, for example:

match_props_on = all_merge_props.flat_map do |key, prop|
  prop.match_on.present? ? prop.match_on.map { |ms| "#{key}.#{ms}" } : []
end

Suggested change

	match_props_on = all_merge_props.filter_map do |key, prop|
	prop.match_on.map { |ms| "#{key}.#{ms}" } if prop.match_on.present?
	end.flatten
	match_props_on = all_merge_props.flat_map do |key, prop|
	prop.match_on.present? ? prop.match_on.map { |ms| "#{key}.#{ms}" } : []
	end