Define AutomationTemplate format and retrieval API (provider templates)

[slombardo]

Design and implement the AutomationTemplate entity and retrieval endpoint, as defined in docs/AutomationAuthoringArchitecture.md.

• Define AutomationTemplate with fields: id, integrationProviderId, name, baseSentence, requiredFieldKeys, ruleCatalog (rule types/templates)
• For M3, persist initial templates as in-memory or static registry (hardcoded, seeded in DB, or config)
• Implement API endpoint: /api/v1/integrationprovider/{providerId}/automation-templates which returns templates for that provider
• Populate with at least Trello Cleaning and Spot Check template examples
• Ensure compatibility with M2 Provider Field Catalog

Exit criteria:

• Code: AutomationTemplate format exists in backend
• Initial (Trello) templates retrievable from the API and visible in API explorer
• Documentation links to docs/AutomationAuthoringArchitecture.md and describes template shape and endpoints