Design deployment strategy configuration schema

**Summary**: Define the YAML schema structure for specifying deployment strategies in azure.yaml, including strategy types, configuration options, and service-specific settings.

**Acceptance Criteria**:
- [ ] YAML schema for deployment strategy configuration with strategy type and parameters
- [ ] Support for service-level and global deployment strategy configuration
- [ ] Schema validation for strategy configuration syntax and compatibility
- [ ] Strategy inheritance from global to service-specific configurations
- [ ] Configuration parameter validation per strategy type
- [ ] JSON schema definition for IDE support and validation