perf(cdk): optimize Jest test suite via shared CDK template synthesis

[scottschreckengaust]

Problem

The CDK Jest test suite takes ~6 minutes (371s) because construct tests re-synthesize CDK templates on every test() block — even when the configuration is identical across tests.

Profiling revealed that task-api.test.ts alone calls Template.fromStack() 41 times (370s wall clock), with each synth taking 5-10s for the TaskApi construct (WAF, Cognito, Lambda, API Gateway).

Solution

Share synthesized Template objects via beforeAll within each describe block. Since CDK Template is read-only (assertions don't mutate), tests with identical input can safely reuse a single template.

Results

Metric	Before	After	Improvement
Total Jest time	371s	145s	61% faster
task-api.test.ts	370s	89s	76% faster
CDK synths in file	41	11	73% fewer

Acceptance criteria

• Refactor task-api.test.ts to use beforeAll shared templates
• All 1789 tests pass (0 failures)
• All 40 tests in task-api.test.ts preserve identical assertions
• (Follow-up) Apply same pattern to task-orchestrator.test.ts (33 synths, 119s)
• (Follow-up) Apply same pattern to ecs-agent-cluster.test.ts (11 synths, 34s)

PR

#195