Fix high prio recommendations, add error / health screen

persistence.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"os"
+	"path/filepath"
+)
+
+func atomicWriteJSON(path string, value any, mode os.FileMode) error {
+	if path == "" {
+		return nil
+	}
+	dir := filepath.Dir(path)
+	if err := os.MkdirAll(dir, 0o700); err != nil {
+		return err
+	}
+	data, err := json.MarshalIndent(value, "", "  ")
+	if err != nil {
+		return err
+	}
+	temp, err := os.CreateTemp(dir, ".gh-threads-*")
+	if err != nil {
+		return err
+	}
+	name := temp.Name()
+	defer os.Remove(name)
+	if err := temp.Chmod(mode); err != nil {
+		_ = temp.Close()
+		return err
+	}
+	if _, err := temp.Write(data); err != nil {
+		_ = temp.Close()
+		return err
+	}
+	if err := temp.Sync(); err != nil {
+		_ = temp.Close()
+		return err
+	}
+	if err := temp.Close(); err != nil {
+		return err
+	}
+	if err := os.Rename(name, path); err != nil {
+		return err
+	}
+	if directory, err := os.Open(dir); err == nil {
+		defer directory.Close()
+		if syncErr := directory.Sync(); syncErr != nil && !errors.Is(syncErr, os.ErrInvalid) {
+			return syncErr
+		}
+	}
+	return nil
+}