Implement new Go based Desktop app

This focuses on Windows first, but coudl be used for Mac
and possibly linux in the future.

app/store/store.go

@@ -0,0 +1,98 @@
+package store
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"log/slog"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/google/uuid"
+)
+
+type Store struct {
+	ID           string `json:"id"`
+	FirstTimeRun bool   `json:"first-time-run"`
+}
+
+var (
+	lock  sync.Mutex
+	store Store
+)
+
+func GetID() string {
+	lock.Lock()
+	defer lock.Unlock()
+	if store.ID == "" {
+		initStore()
+	}
+	return store.ID
+
+}
+
+func GetFirstTimeRun() bool {
+	lock.Lock()
+	defer lock.Unlock()
+	if store.ID == "" {
+		initStore()
+	}
+	return store.FirstTimeRun
+}
+
+func SetFirstTimeRun(val bool) {
+	lock.Lock()
+	defer lock.Unlock()
+	if store.FirstTimeRun == val {
+		return
+	}
+	store.FirstTimeRun = val
+	writeStore(getStorePath())
+}
+
+// lock must be held
+func initStore() {
+	storeFile, err := os.Open(getStorePath())
+	if err == nil {
+		defer storeFile.Close()
+		err = json.NewDecoder(storeFile).Decode(&store)
+		if err == nil {
+			slog.Debug(fmt.Sprintf("loaded existing store %s - ID: %s", getStorePath(), store.ID))
+			return
+		}
+	} else if !errors.Is(err, os.ErrNotExist) {
+		slog.Debug(fmt.Sprintf("unexpected error searching for store: %s", err))
+	}
+	slog.Debug("initializing new store")
+	store.ID = uuid.New().String()
+	writeStore(getStorePath())
+}
+
+func writeStore(storeFilename string) {
+	ollamaDir := filepath.Dir(storeFilename)
+	_, err := os.Stat(ollamaDir)
+	if errors.Is(err, os.ErrNotExist) {
+		if err := os.MkdirAll(ollamaDir, 0o755); err != nil {
+			slog.Error(fmt.Sprintf("create ollama dir %s: %v", ollamaDir, err))
+			return
+		}
+	}
+	payload, err := json.Marshal(store)
+	if err != nil {
+		slog.Error(fmt.Sprintf("failed to marshal store: %s", err))
+		return
+	}
+	fp, err := os.OpenFile(storeFilename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o755)
+	if err != nil {
+		slog.Error(fmt.Sprintf("write store payload %s: %v", storeFilename, err))
+		return
+	}
+	defer fp.Close()
+	if n, err := fp.Write(payload); err != nil || n != len(payload) {
+		slog.Error(fmt.Sprintf("write store payload %s: %d vs %d -- %v", storeFilename, n, len(payload), err))
+		return
+	}
+	slog.Debug("Store contents: " + string(payload))
+	slog.Info(fmt.Sprintf("wrote store: %s", storeFilename))
+}