[v4] Activate Grant Cards

[thedev132]

Summary of the problem

I wanna have the ability to activate grant cards on mobile (kinda how we have org invites).

Describe your changes

I copied most of the logical from the web controller and tweaked it for the API. Then you can activate via /api/v4/card_grants/xxxxxxx/activate

hcb/app/controllers/card_grants_controller.rb

Lines 147 to 157 in 841c978

	def activate
	authorize @card_grant
	@card_grant.create_stripe_card(current_session)
	redirect_to @card_grant
	rescue Stripe::InvalidRequestError => e
	redirect_to @card_grant, flash: { error: "This card could not be activated: #{e.message}" }
	rescue Errors::StripeInvalidNameError => e
	redirect_to @card_grant, flash: { error: e.message }
	end