Fix/jsonapi nested eager loaded leak

[YoussefMansour9]

Prevent unrequested nested eager-loaded relationships from appearing in the included section of JSON:API resource responses.

Fixes #60126

Bug: When a resource is loaded with nested eager-loading like Post::with('comments.commenter')->find($id) and only include=comments is requested, the commenter relation leaks into included. This happens because compileIncludedNestedRelationshipsMap pre-populates ALL loaded model relations, and array_push in resolveIncludedResourceObjects propagates them regardless of the include query.

Changes:

• Thread sub-include paths through the compile chain so each sub-resource knows which relations were actually requested via the include query.
• Rewrite compileIncludedNestedRelationshipsMap to check against the parsed include query instead of all loaded model relations.
• Scope sub-resource resolution via a resolutionSparseIncluded property to prevent includePreviouslyLoadedRelationships from compiling unrequested eager-loaded relations.
• Remove array_push in resolveIncludedResourceObjects since all intended nested entries are pre-populated during the initial compile.
• Fix resolveResourceType Stringable return type.
• Update chaperone test: inverse relations set by chaperone() are no longer automatically included unless explicitly in the include query.
• Add test verifying that include=comments does not leak comments.commenter into included.

[taylorotwell]

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