Add ability to rename lifecycle and Usage section

What does this MR do and why?

1. This MR changes the lifecycle details on custom status settings page behind the work_item_status_mvc2 FF
2. This MR lets users rename a lifecycle

The changes behind this MR are behind the FF so it should not change anything on production

References

Screenshots or screen recordings

With FF switched off	With FF Switched on

With lifecycles with associated work item types	With lifecycles not associated to work item types
Screen Recording 2025-08-15 at 12.40.56 PM.mov	Screen Recording 2025-08-15 at 12.39.58 PM.mov

How to set up and validate locally

1. Enable work_item_status_mvc2 FF

2. To test more lifecycles try the following script in rails console

   namespace = Group.find(98) #id of the group you want to create a namespace
   # Statuses will have random names
   FactoryBot.create(:work_item_custom_lifecycle, namespace: namespace)
   
   
   # 15 refers to the number of lifecycles you want to create
   15.times do
     FactoryBot.create(:work_item_custom_lifecycle, namespace: namespace)
   end

   3. See that when you rename a lifecycle , it is reflected

MR acceptance checklist

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Related to #558219 (closed)