test: ephemeral deployment integration test — verify datasource.active=false with persistence-memory

[mdproctor]

Context

The persistence-memory spec (Refs #191) requires an integration test that boots with persistence-memory on the classpath and these properties:

quarkus.datasource.active=false
quarkus.hibernate-orm.active=false

The test verifies CRUD works through the in-memory stores without any datasource. The result determines which ephemeral deployment config to recommend in the module README.

Scope

• Add casehub-work-persistence-memory as a dependency in a test profile or separate test module
• Boot Quarkus with the deactivation properties
• Exercise WorkItem CRUD through the REST API
• Verify no datasource validation errors at startup

If deactivation doesn't work cleanly, fall back to the H2 dummy datasource config documented in the spec.

Found during

Implementation planning for #191 — flagged as follow-on since it requires integration test infrastructure changes.

Refs #191