postgres: announce a consumer failed for minutes, and its recovery

A provider failed every consumer for a day and said so only in its journal
(hq issue 179). The provisioner loop now emits provisioner.failing after five
minutes without a success — create, check or secret — and repeats it every
fifteen; provisioner.recovered on the next success, on withdrawal, and on the
first success after a restart, so the controller can name it in status
(hq ADR 0224).

modules/postgres/cmd/postgres-provider/harness_same_test.go

@@ -0,0 +1,31 @@
+package main
+
+// The provisioner loop is carried, identical, by every Go provider until the Go SDK has it
+// (harness.go). Two copies drift the moment one is fixed and the other is not — and the one left
+// behind is the provider that fails a consumer without saying so (novox/hq ADR 0224). This holds
+// them to one text. Skipped where keycloak is not beside this module, as in a build of this one alone.
+
+import (
+	"bytes"
+	"errors"
+	"io/fs"
+	"os"
+	"testing"
+)
+
+func TestTheHarnessIsTheSameAsKeycloaks(t *testing.T) {
+	theirs, err := os.ReadFile("../../../keycloak/cmd/keycloak-provider/harness.go")
+	if errors.Is(err, fs.ErrNotExist) {
+		t.Skip("keycloak is not beside this module")
+	}
+	if err != nil {
+		t.Fatal(err)
+	}
+	ours, err := os.ReadFile("harness.go")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(ours, theirs) {
+		t.Fatal("harness.go differs from keycloak/cmd/keycloak-provider/harness.go: change both, identically")
+	}
+}