Fix exists() type safety and error handling

Address code review feedback on PR #152:
- Fix TypeScript compilation by importing FileExistsRequest from @repo/shared
- Add sessionId parameter to ISandbox.exists() for API consistency
- Fix error handling to propagate execution failures properly

Co-authored-by: Naresh <[email protected]>

Author: github-actions[bot]

packages/sandbox-container/src/handlers/file-handler.ts

@@ -1,5 +1,6 @@
 import type {
   DeleteFileResult,
+  FileExistsRequest,
   FileExistsResult,
   FileStreamEvent,
   ListFilesResult,Logger,
@@ -13,7 +14,6 @@ import { ErrorCode } from '@repo/shared/errors';
 
 import type {
   DeleteFileRequest,
-  FileExistsRequest,
   ListFilesRequest,
   MkdirRequest,
   MoveFileRequest,

packages/sandbox-container/src/services/file-service.ts

@@ -721,10 +721,17 @@ export class FileService implements FileSystemOperations {
       const execResult = await this.sessionManager.executeInSession(sessionId, command);
 
       if (!execResult.success) {
-        // If execution fails, treat as non-existent
+        // If command execution fails, propagate the error
         return {
-          success: true,
-          data: false
+          success: false,
+          error: {
+            message: `Failed to check file existence for '${path}': Command execution failed`,
+            code: ErrorCode.FILESYSTEM_ERROR,
+            details: {
+              path,
+              operation: Operation.FILE_STAT
+            } satisfies FileSystemContext
+          }
         };
       }
 

packages/shared/src/types.ts

@@ -655,7 +655,7 @@ export interface ISandbox {
   renameFile(oldPath: string, newPath: string): Promise<RenameFileResult>;
   moveFile(sourcePath: string, destinationPath: string): Promise<MoveFileResult>;
   listFiles(path: string, options?: ListFilesOptions): Promise<ListFilesResult>;
-  exists(path: string): Promise<FileExistsResult>;
+  exists(path: string, sessionId?: string): Promise<FileExistsResult>;
 
   // Git operations
   gitCheckout(repoUrl: string, options?: { branch?: string; targetDir?: string }): Promise<GitCheckoutResult>;