feat(filetree): add filesystem watch support to WebContainer environment and auto-refresh file tree; improve icon handling and context menu behavior

ts_web/elements/00group-runtime/interfaces/IExecutionEnvironment.ts

@@ -7,6 +7,14 @@ export interface IFileEntry {
   path: string;
 }
 
+/**
+ * Handle to a file system watcher
+ */
+export interface IFileWatcher {
+  /** Stop watching for changes */
+  stop(): void;
+}
+
 /**
  * Handle to a spawned process with I/O streams
  */
@@ -68,6 +76,19 @@ export interface IExecutionEnvironment {
    */
   exists(path: string): Promise<boolean>;
 
+  /**
+   * Watch a file or directory for changes
+   * @param path - Absolute path to watch
+   * @param callback - Called when changes occur
+   * @param options - Optional: { recursive: true } to watch subdirectories
+   * @returns Watcher handle with stop() method
+   */
+  watch(
+    path: string,
+    callback: (event: 'rename' | 'change', filename: string | null) => void,
+    options?: { recursive?: boolean }
+  ): IFileWatcher;
+
   // ============ Process Execution ============
 
   /**