feat(ecs): add capacityOptionType (Spot support) to ManagedInstancesCapacityProvider L2 construct

[djglaser]

Issue # (if applicable)

Relates public PR #35648

Description of changes

ECS is expanding configuration options for a ManagedInstances CapacityProvider by allowing users to set a CapacityOptionType. This is an enum with allowed values of ON_DEMAND and SPOT. This attribute falls under the existing ManagedInstancesCapacityProvider L2 construct.

Feature description

Capacity Option Type provides the purchasing option for the EC2 instances used in the capacity provider. Determines whether to use On-Demand or Spot instances. Valid values are ON_DEMAND and SPOT. Defaults to ON_DEMAND when not specified. Changing this value will trigger replacement of the capacity provider. For more information, see Amazon EC2 billing and purchasing options in the Amazon EC2 User Guide.

Description of how you validated changes

• Added and validated unit tests
• Modified existing ManagedInstances integration test to include a CapacityOptionType attribute with a value of SPOT.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[github-actions]

⚠️ Experimental Feature: This security report is currently in experimental phase. Results may include false positives and the rules are being actively refined.
Please try merge from main to avoid findings unrelated to the PR.

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	Tests	Passed ☑️	Skipped	Failed ❌️
Security Guardian Results	25 ran	24 passed		1 failed

Test	Result
Security Guardian Results
packages/@aws-cdk-testing/framework-integ/test/aws-ecs/test/integ.managedinstances-capacity-provider.js.snapshot/integ-managedinstances-capacity-provider.template.json
ec2-no-open-security-groups.guard	❌ failure

• View Security Guardian Results

[github-actions]

⚠️ Experimental Feature: This security report is currently in experimental phase. Results may include false positives and the rules are being actively refined.
Please try merge from main to avoid findings unrelated to the PR.

---

	Tests	Passed ✅	Skipped	Failed
Security Guardian Results with resolved templates	25 ran	25 passed

Test	Result
No test annotations available

• View Security Guardian Results with resolved templates