fix: make the host function installation generic

[JakubGonera]

Description

Make the model host function installation generic, so that you can easily introduce additional methods that resolve with a promise.

Tested on

• iOS
• Android

Related issues

#255

Checklist

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have updated the documentation accordingly
• My changes generate no new warnings

[Copilot]

Pull Request Overview

This pull request refactors host function installation to be more generic by allowing promise-based function resolution. It updates the macro in JsiHostObject.h to accept a custom name and refactors ModelHostObject.h to use a templated host function for forwarding calls.

• Updated JSI_EXPORT_FUNCTION macro to include a NAME parameter.
• Refactored ModelHostObject to use a templated promiseHostFunction and updated error handling.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
common/rnexecutorch/jsi/JsiHostObject.h	Updated macro to include a NAME parameter for improved clarity.
common/rnexecutorch/host_objects/ModelHostObject.h	Refactored the host function to a generic templated version and adjusted argument count checks and error message formatting.

Comments suppressed due to low confidence (2)

common/rnexecutorch/host_objects/ModelHostObject.h:37

• [nitpick] Consider using a std::string or another dynamic string formatting approach to construct the error message to avoid fixed buffer size constraints and potential overflow issues.

char errorMessage[100];

common/rnexecutorch/jsi/JsiHostObject.h:18

• [nitpick] Ensure that all invocations of JSI_EXPORT_FUNCTION in the codebase are updated to pass the additional NAME parameter so that the changes remain consistent and clear.

#define JSI_EXPORT_FUNCTION(CLASS, FUNCTION, NAME)