fix: implement map line_type_intelligence snake_case fields to camelCase in constructor for PhoneNumberInstance

[victorlunam]

Fixes #1148

Description

This PR fixes a bug where line_type_intelligence fields returned from the Lookups API (in snake_case) were not mapped to the camelCase properties expected by the PhoneNumberInstance class.

Breaking Change:
This change creates a new object for lineTypeIntelligence rather than assigning the raw payload.

• Previously: The object contained snake_case keys (e.g., mobile_country_code) at runtime, while the TypeScript definitions existed for camelCase (e.g., mobileCountryCode) but returned undefined.
• Now: The object correctly contains camelCase keys. Any integrations relying on the undocumented/untyped snake_case keys at runtime will break and must be updated to use the camelCase equivalents.

What was changed

• Updated the PhoneNumberInstance constructor to manually map line_type_intelligence properties:
  • mobile_country_code → mobileCountryCode
  • mobile_network_code → mobileNetworkCode
  • carrier_name → carrierName
  • type → type
  • error_code → errorCode
• Ensured strict camelCase adherence to match the LineTypeIntelligenceInfo interface.

Why the change was necessary

The PhoneNumberInstance was assigning the raw API response directly to the class property, causing a mismatch between the TypeScript definitions (camelCase) and the runtime values (snake_case). This resulted in undefined values when using the typed properties.

Checklist

• I acknowledge that all my contributions will be made under the project's license
• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the Contribution Guidelines and my PR follows them
• I have titled the PR appropriately
• I have updated my branch with the main branch
• I have added tests that prove my fix is effective or that my feature works
• I have added the necessary documentation about the functionality in the appropriate .md file
• I have added inline documentation to the code I modified