fix: complete target diagnostics and reset inspection

internal/dockerclient/dockerclient_test.go

@@ -44,6 +44,29 @@ func TestAvailabilityAndDescriptionDescribeOnlyDockerClientDefaults(t *testing.T
 	}
 }
 
+func TestDiagnosticChecksCoverSchemaAndAuthorityWithoutMutation(t *testing.T) {
+	files := &countingFS{FileSystem: dockerclient.OSFileSystem{}}
+	a := newAdapterWithFS(t, files)
+	checks := a.DiagnosticChecks(context.Background(), activeProfile())
+	for _, name := range []string{"required commands", "configuration schema", "write authority"} {
+		found := false
+		for _, check := range checks {
+			found = found || check.Name == name
+		}
+		if !found {
+			t.Errorf("diagnostics missing %q: %#v", name, checks)
+		}
+	}
+	if files.writes != 0 {
+		t.Fatalf("diagnostics wrote Docker client state %d times", files.writes)
+	}
+	for _, path := range []string{a.ConfigPath(), a.RecoveryPath(), a.LockPath()} {
+		if _, err := os.Stat(path); !errors.Is(err, os.ErrNotExist) {
+			t.Fatalf("diagnostics created %s: %v", path, err)
+		}
+	}
+}
+
 func TestDockerClientAdapterRunsReusableTargetContract(t *testing.T) {
 	targettest.Run(t, func(t *testing.T) targettest.Fixture {
 		a := newAdapter(t, nil)