feat: publish standalone worker

Separate worker packaging and service lifecycle from the control plane.

internal/webapp/cteq.go

@@ -0,0 +1,10 @@
+package webapp
+
+import "crypto/subtle"
+
+// constantTimeEq is a thin wrapper around crypto/subtle.ConstantTimeCompare
+// so the middleware file does not need an extra import for a single
+// call.
+func constantTimeEq(a, b string) int {
+	return subtle.ConstantTimeCompare([]byte(a), []byte(b))
+}