[pietro909]

Master already renamed delegatee to executor. This adds what the executor expects on top:

• executor-initdb one-shot creates the executor database; EXECUTOR_DATABASE_URL uses it instead of postgres's default one
• executor added to the CI failure-diagnostics container list

[arkana-ai-bot]

Arkana review — infra/devops, no protocol code

Changes: docker/compose.ark.yml, .github/workflows/ci.yml, README.md.

Overall

Clean, low-risk infrastructure change. The executor-initdb service is an exact structural copy of the established bucket-sync-initdb pattern, it's idempotent (checks before creating), and the executor service correctly gates on service_completed_successfully. No protocol code, no VTXO/signing/round/exit paths touched.

Specific findings

Minor: executor-initdb absent from CI failure-diagnostics loop
docker/compose.ark.yml — executor-initdb service
.github/workflows/ci.yml:248

The loop was updated to add executor but not executor-initdb. If initdb fails (e.g., can't reach postgres, bad credentials), the CI dump won't capture its logs and the root cause will be invisible. executor will be Created but never started (dependency failed), so its own log line will be empty — the useful log is on executor-initdb. Same gap already exists for bucket-sync-initdb on failure, but adding executor-initdb alongside executor here would close it for the new service.

Nit: stale delegatee service still uses the default postgres database
docker/compose.ark.yml:291–304

Pre-existing, not introduced by this PR, but worth flagging while context is warm: the old delegatee service (profile delegatee) still points DELEGATEE_DATABASE_URL at postgres://postgres@postgres:5432/postgres (the default database), while every other service that needs postgres has either autocreate or its own initdb. If delegatee is dead code pending removal it's harmless; if it's still exercised anywhere it would need the same treatment as executor got here.

Observation: executor image is still a release-candidate tag (v0.0.4-rc.1)
docker/compose.ark.yml:321

Pre-existing pin, not changed by this PR. Flagging so it doesn't get forgotten once a stable tag ships.

Summary

One small actionable item (add executor-initdb to the CI diagnostics loop); everything else is contextual. The core pattern is correct and the change is safe to land.