Update roadmap

Author: jamescmartinez

packages/docs/docs/roadmap.mdx

@@ -8,6 +8,7 @@ description: What's coming next for OpenWorkflow
 - ✅ PostgreSQL and SQLite backends
 - ✅ CLI (`npx @openworkflow/cli`)
 - ✅ Dashboard (`npx @openworkflow/cli dashboard`)
+- ✅ Bun runtime support
 - ✅ Worker with concurrency control
 - ✅ Step memoization & retries
 - ✅ Graceful shutdown
@@ -20,9 +21,13 @@ description: What's coming next for OpenWorkflow
 
 ## Coming Soon
 
+- Prometheus metrics endpoint
+- Child workflows
+- Signals
+- Cron / scheduling
 - Rollback / compensation functions
-- Signals for external events
-- Native OpenTelemetry integration
+- Priority and concurrency controls
+- OpenTelemetry
 - Additional backends (Redis)
 - Additional languages (Go, Python)