Backend: Compliance Framework Templates
## Overview
Implement backend support for compliance framework templates.
## Scope
- Database schema migration: Add `template_id` and `template_version` fields to compliance frameworks table
- Template registry: Create `ee/lib/compliance_management/frameworks/template_registry.rb` to manage available templates
- Template data files: Create template JSON files (e.g., `ee/config/compliance_management/templates/soc2.json`)
- CreateFromTemplateService: Implement new service to load templates, merge user overrides, and create frameworks
- JsonImportService enhancement: Extend to pass through `template_id` and `template_version`
- CreateService enhancement: Add `template_id` and `template_version` to attribute assignment
- Framework update logic: Implement logic to null out template fields when framework is edited (disconnecting from future updates)
- Banner/warning system: Add notification when editing a templated framework
## Implementation Details
Refer to the technical implementation plan in #534615 for detailed specifications.
issue