feat: add missing Tickets entity fields from Autotask API

Added 10 critical missing fields to Tickets entity:

Database Migration (016):
- billing_code_id: Billing code assignment
- configuration_item_id: Primary asset/CI
- creator_resource_id: Ticket creator
- creator_type: Creator type (resource/contact)
- problem_ticket_id: Link to problem ticket
- rma_status: RMA status tracking
- rma_type: RMA type classification
- service_level_agreement_paused_next_event_hours: SLA pause tracking
- is_assigned_to_comanaged: Co-managed assignment flag
- is_visible_to_comanaged: Co-managed visibility flag

Entity Mapper Updates:
- Added all new fields with correct camelCase mapping
- Ensures all Autotask Tickets API fields are captured

This completes the Tickets entity to match the full Autotask API
specification and should resolve issues with missing ticket data.

migrations/016_add_missing_tickets_fields.sql

@@ -0,0 +1,28 @@
+-- Add missing fields to tickets table based on Autotask Tickets API
+-- Reference: https://autotask.net/help/developerhelp/Content/APIs/REST/Entities/TicketsEntity.htm
+
+ALTER TABLE tickets
+  -- Billing and configuration
+  ADD COLUMN IF NOT EXISTS billing_code_id BIGINT,
+  ADD COLUMN IF NOT EXISTS configuration_item_id BIGINT,
+  
+  -- Creator information
+  ADD COLUMN IF NOT EXISTS creator_resource_id BIGINT,
+  ADD COLUMN IF NOT EXISTS creator_type INTEGER,
+  
+  -- Problem/incident tracking
+  ADD COLUMN IF NOT EXISTS problem_ticket_id BIGINT,
+  
+  -- RMA fields
+  ADD COLUMN IF NOT EXISTS rma_status INTEGER,
+  ADD COLUMN IF NOT EXISTS rma_type INTEGER,
+  
+  -- SLA tracking
+  ADD COLUMN IF NOT EXISTS service_level_agreement_paused_next_event_hours DECIMAL(10,2),
+  
+  -- Co-managed fields
+  ADD COLUMN IF NOT EXISTS is_assigned_to_comanaged BOOLEAN DEFAULT false,
+  ADD COLUMN IF NOT EXISTS is_visible_to_comanaged BOOLEAN DEFAULT false;
+
+-- Add comment to track migration
+COMMENT ON TABLE tickets IS 'Added missing Autotask API fields - Migration 016';