handle empty path strings in fs polyfill and remove redundant comment in worker command

Author: mavdol

crates/capsule-cli/src/commands/worker.rs

@@ -73,7 +73,6 @@ pub async fn execute() -> Result<(), WorkerError> {
     let runtime = Runtime::new(runtime_config, capsule_toml)
         .map_err(|e| WorkerError::RuntimeError(e.to_string()))?;
 
-    // Cache wasm_path per source file so fingerprint checks only run once per file.
     let wasm_cache: Arc<Mutex<HashMap<String, PathBuf>>> = Arc::new(Mutex::new(HashMap::new()));
 
     let stdin = tokio::io::stdin();

crates/capsule-sdk/javascript/src/polyfills/fs.ts

@@ -78,7 +78,7 @@ function normalizePath(path: string): string {
     else if (p.startsWith('/')) p = p.slice(1);
     if (p.length > 1) p = p.replace(/\/+$/, '');
 
-    return p;
+    return p || '.';
 }
 
 /**