IntentEngineIT cleanup leaves a generated project published, making the bootstrap test order-dependent

[ThuF]

Goal

Keep the intent engine's integration tests trustworthy: a test that passes alone must not start failing because another test in the same class ran first.

Scope

• In scope: complete the per-test cleanup in IntentEngineIT so a test leaves no state behind for the next one, and state the precondition the mutual cross-model bootstrap test depends on.
• Out of scope: changing when a Generate publishes, and changing what deleting a workspace project does to the published copy - both are deliberate platform behaviour.

Description

A Generate publishes the project it generated, so a test that generates the shared dependency project leaves a published copy behind that the class's cleanup never removed. The next test then resolves its cross-model owner against the previous test's output and quietly takes a different path - the bootstrap test for #6539 stops seeing the refusal it exists to assert.

Acceptance Criteria

• Every test in the class starts from a workspace and a registry that hold none of its projects.
• The mutual cross-model bootstrap test asserts that precondition, so a future collision fails saying why.
• The class is green both as a whole and when only the affected tests are selected.

Dependencies

• intent: a mutual cross-model generates cycle cannot bootstrap fresh (lazy target resolution or declared two-pass) #6539