fix: add local static file storage fallback

apps/api/internal/httpapi/static_assets.go

@@ -0,0 +1,37 @@
+package httpapi
+
+import (
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/easyai/easyai-ai-gateway/apps/api/internal/config"
+)
+
+func (s *Server) serveGeneratedStaticAsset(w http.ResponseWriter, r *http.Request) {
+	s.serveLocalStaticAsset(w, r, s.cfg.LocalGeneratedStorageDir, config.DefaultLocalGeneratedStorageDir)
+}
+
+func (s *Server) serveUploadedStaticAsset(w http.ResponseWriter, r *http.Request) {
+	s.serveLocalStaticAsset(w, r, s.cfg.LocalUploadedStorageDir, config.DefaultLocalUploadedStorageDir)
+}
+
+func (s *Server) serveLocalStaticAsset(w http.ResponseWriter, r *http.Request, storageDir string, fallbackStorageDir string) {
+	fileName := filepath.Base(strings.TrimSpace(r.PathValue("asset")))
+	if fileName == "" || fileName == "." || fileName == ".." || fileName == string(filepath.Separator) {
+		http.NotFound(w, r)
+		return
+	}
+	storageDir = strings.TrimSpace(storageDir)
+	if storageDir == "" {
+		storageDir = fallbackStorageDir
+	}
+	filePath := filepath.Join(storageDir, fileName)
+	info, err := os.Stat(filePath)
+	if err != nil || info.IsDir() {
+		http.NotFound(w, r)
+		return
+	}
+	http.ServeFile(w, r, filePath)
+}