feat: publish standalone worker

Separate worker packaging and service lifecycle from the control plane.

checks/calls/init_test.go

@@ -0,0 +1,11 @@
+package calls
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIsDBAvailableWithoutInitializedDatabase(t *testing.T) {
+	assert.False(t, isDBAvailable())
+}