Don't overwrite when a file has already been staged to dist

src/build/run.mjs

@@ -58,7 +58,7 @@ function stageStaticContent(srcDir, destDir) {
         fs.ensureDir(path.dirname(destPath))
             .then(() => {
                 // Copy the file to the new destination
-                fs.copy(file, destPath).catch((err) => console.error(`Error copying file ${file}:`, err));
+                fs.copy(file, destPath, { overwrite: false}).catch((err) => console.error(`Error copying file ${file}:`, err));
             })
             .catch((err) => console.error(`Error creating directory for ${destPath}:`, err));
     });