Add REST API endpoints for programmatic PBX configuration

[dmzoneill]

freepbx currently relies heavily on the web UI for configuration. having a REST API would make it easier to:

• automate bulk extension creation from external systems
• integrate with provisioning tools like ansible or terraform
• sync configurations across multiple pbx instances
• implement custom management dashboards

useful endpoints could include:

• GET/POST /extensions for reading and creating extensions
• GET/POST /trunks for trunk management
• GET/POST /routes for inbound and outbound routes
• authentication via API tokens

this would complement the existing AMI/AGI interfaces which are more focused on call control than configuration management.

interested?