Function isRgb256ColorSupported

isRgb256ColorSupported(): boolean
Returns true if the terminal supports at least 256 colors, but may support more.

Returns boolean
True if the terminal supports 256 colors
Example
```
import { isRgb256ColorSupported } from "@nevware21/chromacon";

if (isRgb256ColorSupported()) {
 console.log("256 colors are supported");
}
```
- Defined in core/src/utils/supported.ts:138