fix(integration-direct/v1): add missing agent-repo/v1 layer

All tasks dispatched to integration-direct/v1 were failing with
harness_missing_agent_repo_layer because dispatcher DSP-1 guard
requires agent-repo in the composite when AGENT_REPO_URL is set.

direct-push/v1 sets env vars (AGENT_SKIP_BRANCH_PUSH,
AGENT_EMPTY_DELIVERABLE_CHECK) that configure agent-repo's finalize.sh,
so agent-repo/v1 must precede it in the layer list.

harnesses/composites/integration-direct/v1/harness.yaml

@@ -7,4 +7,5 @@ layers:
   - context: integration/v1
   - context: anthropic-cloud-paul-oauth/v1
   - context: gitea-ssh/v1
+  - context: agent-repo/v1
   - context: direct-push/v1