feat: add number/float16/base/identity

[Neerajpathak07]

Resolves #none.

Description

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This pull request:

• Adds number/float16/base/identity

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This pull request has the following related issues:

• none

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---

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[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
number/float16/base/identity	$\color{green}106/106$ $\color{green}+0.00%$	$\color{green}3/3$ $\color{green}+0.00%$	$\color{green}1/1$ $\color{green}+0.00%$	$\color{green}106/106$ $\color{green}+0.00%$

The above coverage report was generated for the changes in this PR.

[Neerajpathak07]

@kgryte for the C implementation I was thinking of writing the addon as:-

#include "stdlib/number/float16/base/identity.h"
#include "stdlib/number/float64/base/to_float16.h"
#include <node_api.h>
#include <stdint.h>
#include <stdbool.h>
#include <assert.h>

/**
* Receives JavaScript callback invocation data.
*
* @param env    environment under which the function is invoked
* @param info   callback data
* @return       Node-API value
*/
static napi_value addon( napi_env env, napi_callback_info info ) {
	napi_status status;

	// Get callback arguments:
	size_t argc = 1;
	napi_value argv[ 1 ];
	status = napi_get_cb_info( env, info, &argc, argv, NULL, NULL );
	assert( status == napi_ok );

	// Check whether we were provided the correct number of arguments:
	if ( argc < 1 ) {
		status = napi_throw_error( env, NULL, "invalid invocation. Insufficient arguments." );
		assert( status == napi_ok );
		return NULL;
	}
	if ( argc > 1 ) {
		status = napi_throw_error( env, NULL, "invalid invocation. Too many arguments." );
		assert( status == napi_ok );
		return NULL;
	}

	napi_valuetype vtype0;
	status = napi_typeof( env, argv[ 0 ], &vtype0 );
	assert( status == napi_ok );
	if ( vtype0 != napi_number ) {
		status = napi_throw_type_error( env, NULL, "invalid argument. First argument must be a number." );
		assert( status == napi_ok );
		return NULL;
	}

	double value;
	status = napi_get_value_double( env, argv[ 0 ], &value );
	assert( status == napi_ok );

	uint16_t out = stdlib_base_float16_identity( stdlib_base_float64_to_float16( value ) );

	napi_value v;
	status = napi_create_int32( env, (uint16_t)out, &v );
	assert( status == napi_ok );

	return v;
}

/**
* Initializes a Node-API module.
*
* @param env      environment under which the function is invoked
* @param exports  exports object
* @return         main export
*/
static napi_value init( napi_env env, napi_value exports ) {
	napi_value fcn;
	napi_status status = napi_create_function( env, "exports", NAPI_AUTO_LENGTH, addon, NULL, &fcn );
	assert( status == napi_ok );
	return fcn;
}

NAPI_MODULE( NODE_GYP_MODULE_NAME, init )

Since we do not have macro support for uint16_t to uint16_t.
Or would you recommend to add the macro instead?