Function isValidMobile

isValidMobile(phone: unknown): boolean
Validates whether the input is a valid Sri Lankan mobile phone number (Dialog, Mobitel, Hutch, Airtel).
Parameters
- phone: unknown
  Phone number to check.
Returns boolean
true only for Sri Lankan mobile numbers.
Example
```
isValidMobile('077 123 4567'); // true
isValidMobile('0112345678'); // false
```
- Defined in phone/validator.ts:53