Phase 4 (Performance) + Phase 6 (Infrastructure) completion

Phase 4 — Performance:
- F1: SSH DialPool with key-by-host pooling and 5min idle TTL
- F2: In-memory entity lookup cache (TTL 60s, HTTP resolveEntityID)
- F3: Trigram GIN indexes on entities.slug and entities.name (migration 031)
- F4: Partial index on executions(classification_id) for auto-act (migration 032)
- Added missing RunOutput and RunStreaming in actuator/ (E3 gap fill)

Phase 6 — Infrastructure:
- H1: Infisical image pinned to v0.99.1
- H2: execworker daemon — polls pending executions with per-execution
  advisory locks, recovers orphaned running executions, wired as
  docker-compose service
- H3: splitSQL hardened with block comment and string-literal support,
  6 new edge-case tests (11 total)
- H4: Scheduler acquires pg_try_advisory_lock(0x01c05e6) at startup

migrations/032_auto_act_index.up.sql

@@ -0,0 +1,8 @@
+-- 032_auto_act_index.up.sql
+-- Add a partial index on executions(classification_id) to support the
+-- GetOpenSignalsForAutoAct anti-join: LEFT JOIN executions e ON
+-- e.classification_id = c.entity_id WHERE e.entity_id IS NULL (F4).
+
+CREATE INDEX IF NOT EXISTS idx_executions_classification
+  ON executions (classification_id)
+  WHERE entity_id IS NOT NULL;