Function getMainCountryForCode

getMainCountryForCode(countryCode: number): Promise<string | undefined>
Gets the main country for a country calling code. For country codes shared by multiple regions (e.g., +1 for US/CA), returns the primary region.
Parameters
- countryCode: number
  The country calling code
Returns Promise<string | undefined>
The main region code or undefined if unknown
Example
```
await getMainCountryForCode(1)   // "US"
await getMainCountryForCode(44)  // "GB"
await getMainCountryForCode(49)  // "DE"
```
- Defined in region.ts:171