Add deepMerge Support for Merging Nested Arrays and Objects in Props

[HichemTab-tech]

This PR introduces support for deepMerge functionality in Inertia.js, enabling developers to merge nested arrays and objects within props when rendering pages. This is particularly useful for situations where complex data structures, such as pagination objects or deeply nested configuration objects, need to be updated incrementally.

Why This Is Useful:

Consider a scenario where you have a pagination object that contains nested properties like data, meta, and links:

{
  data: [/* items */],
  meta: { /* pagination metadata */ },
  links: { /* pagination links */ }
}

With deepMerge, the data array can be properly merged by appending new items, while other nested properties like meta and links are also updated incrementally. This ensures that only the necessary parts of the pagination object are modified without replacing the entire object, which can help maintain the consistency of the data across requests.

Related PR:

This PR works in conjunction with the newly added deep merging logic in the Inertia-laravel repository. Please see inertia-laravel PR #679 for details on the client-side implementation.

Related Issue:

• Inertia::merge() Improperly Merges Pagination Objects in Inertia v2 #2068

[HichemTab-tech]

Hi, any progress here ?! We really need this feature enhancement. Thanks.