feat: implement single POST upsert API with automatic ID generation

- Replace separate POST/PUT endpoints with unified POST upsert
- Add automatic content ID generation from element context when no ID provided
- Implement version history preservation before content updates
- Add element context support for backend ID generation
- Update frontend to use single endpoint for all content operations
- Enhanced demo site with latest database content including proper content IDs

internal/api/handlers.go

@@ -252,68 +252,6 @@ func (h *ContentHandler) CreateContent(w http.ResponseWriter, r *http.Request) {
 	}
 	userID := userInfo.ID
 
-	var content interface{}
-	var err error
-
-	switch h.database.GetDBType() {
-	case "sqlite3":
-		content, err = h.database.GetSQLiteQueries().CreateContent(context.Background(), sqlite.CreateContentParams{
-			ID:           contentID,
-			SiteID:       siteID,
-			Value:        req.Value,
-			Type:         req.Type,
-			LastEditedBy: userID,
-		})
-	case "postgresql":
-		content, err = h.database.GetPostgreSQLQueries().CreateContent(context.Background(), postgresql.CreateContentParams{
-			ID:           contentID,
-			SiteID:       siteID,
-			Value:        req.Value,
-			Type:         req.Type,
-			LastEditedBy: userID,
-		})
-	default:
-		http.Error(w, "Unsupported database type", http.StatusInternalServerError)
-		return
-	}
-
-	if err != nil {
-		http.Error(w, fmt.Sprintf("Failed to create content: %v", err), http.StatusInternalServerError)
-		return
-	}
-
-	item := h.convertToAPIContent(content)
-
-	w.Header().Set("Content-Type", "application/json")
-	w.WriteHeader(http.StatusCreated)
-	json.NewEncoder(w).Encode(item)
-}
-
-// UpdateContent handles PUT /api/content/{id} with upsert functionality
-func (h *ContentHandler) UpdateContent(w http.ResponseWriter, r *http.Request) {
-	vars := mux.Vars(r)
-	contentID := vars["id"]
-	siteID := r.URL.Query().Get("site_id")
-
-	if siteID == "" {
-		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
-		return
-	}
-
-	var req UpdateContentRequest
-	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
-		http.Error(w, "Invalid JSON", http.StatusBadRequest)
-		return
-	}
-
-	// Extract user from request using authentication service
-	userInfo, authErr := h.authService.ExtractUserFromRequest(r)
-	if authErr != nil {
-		http.Error(w, fmt.Sprintf("Authentication error: %v", authErr), http.StatusUnauthorized)
-		return
-	}
-	userID := userInfo.ID
-
 	// Check if content exists for version history (non-blocking)
 	var existingContent interface{}
 	var contentExists bool
@@ -350,13 +288,12 @@ func (h *ContentHandler) UpdateContent(w http.ResponseWriter, r *http.Request) {
 		contentType = "text" // default type for new content
 	}
 
-	// Perform upsert operation
-	var upsertedContent interface{}
+	var content interface{}
 	var err error
 
 	switch h.database.GetDBType() {
 	case "sqlite3":
-		upsertedContent, err = h.database.GetSQLiteQueries().UpsertContent(context.Background(), sqlite.UpsertContentParams{
+		content, err = h.database.GetSQLiteQueries().UpsertContent(context.Background(), sqlite.UpsertContentParams{
 			ID:           contentID,
 			SiteID:       siteID,
 			Value:        req.Value,
@@ -364,7 +301,7 @@ func (h *ContentHandler) UpdateContent(w http.ResponseWriter, r *http.Request) {
 			LastEditedBy: userID,
 		})
 	case "postgresql":
-		upsertedContent, err = h.database.GetPostgreSQLQueries().UpsertContent(context.Background(), postgresql.UpsertContentParams{
+		content, err = h.database.GetPostgreSQLQueries().UpsertContent(context.Background(), postgresql.UpsertContentParams{
 			ID:           contentID,
 			SiteID:       siteID,
 			Value:        req.Value,
@@ -381,7 +318,7 @@ func (h *ContentHandler) UpdateContent(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	item := h.convertToAPIContent(upsertedContent)
+	item := h.convertToAPIContent(content)
 
 	// Trigger file enhancement if site is registered for auto-enhancement
 	if h.siteManager != nil && h.siteManager.IsAutoEnhanceEnabled(siteID) {
@@ -395,6 +332,7 @@ func (h *ContentHandler) UpdateContent(w http.ResponseWriter, r *http.Request) {
 	}
 
 	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusCreated)
 	json.NewEncoder(w).Encode(item)
 }
 

internal/api/models.go

@@ -50,12 +50,6 @@ type CreateContentRequest struct {
 	CreatedBy      string          `json:"created_by,omitempty"`
 }
 
-type UpdateContentRequest struct {
-	Value     string `json:"value"`
-	Type      string `json:"type,omitempty"`
-	UpdatedBy string `json:"updated_by,omitempty"`
-}
-
 type RollbackContentRequest struct {
 	VersionID    int64  `json:"version_id"`
 	RolledBackBy string `json:"rolled_back_by,omitempty"`