refactor: Update form field identifiers and improve URL handling for NextCloud and WebDAV

- Changed input field IDs and names from 'dest_endpoint' and 'source_endpoint' to 'dest_host' and 'source_host' for consistency across NextCloud and WebDAV forms.
- Updated placeholder texts for username, password, and file path fields to be more user-friendly.
- Enhanced the URL parsing and validation logic in the transfer configuration generation to ensure proper handling of WebDAV and NextCloud URLs, improving robustness and error handling.

internal/web/handlers/config_handlers.go

@@ -286,6 +286,7 @@ func (h *Handlers) HandleCreateConfig(c *gin.Context) {
 	}
 
 	// Generate rclone config file
+
 	if err := h.DB.GenerateRcloneConfig(&config); err != nil {
 		log.Printf("Warning: Failed to generate rclone config: %v", err)
 		// Continue anyway, as the config was created in the database