Fix view engine path resolution

lib/src/unit/ViewEngine.ts

@@ -95,7 +95,15 @@ export default class ViewEngine extends LifecycleUnit {
      */
     public template_path(...parts: string[]): string {
         if ( !this.template_dir ) throw new MissingTemplateDirectoryError()
-        return path.resolve(this.template_dir, ...parts)
+        let template_dir = this.template_dir
+        if ( template_dir.startsWith('file://') ) template_dir = template_dir.slice(7)
+
+        const resolved_path = path.resolve(template_dir, ...parts)
+        if ( resolved_path.startsWith('/') ) {
+            return `file://${resolved_path}`
+        } else {
+            return resolved_path
+        }
     }
 
     /**