Function I64

I64(value: bigint): RelishI64
Creates a signed 64-bit integer Relish value using JavaScript BigInt.

Use for large signed integers that exceed JavaScript's safe integer range (±2^53-1).
Parameters
- value: bigint
  BigInt in range -9223372036854775808 to 9223372036854775807
Returns RelishI64
RelishI64 value
Throws
Error if value is out of range
Example
```
import { I64 } from '@grounds/core';

const valid = I64(BigInt('-9007199254740992'));
const max = I64(BigInt('9223372036854775807'));
const min = I64(BigInt('-9223372036854775808'));

// Runtime errors:
// I64(BigInt('-9223372036854775809')) // Error: out of range
// I64(BigInt('9223372036854775808'))  // Error: out of range
```
See
- I32 for 32-bit signed
- I128 for 128-bit signed