fix(storage): idempotent rm/mv operations with vector index sync

[SeanZ]

Description

Make file deletion (rm) and move (mv) operations idempotent, ensuring vector index consistency. When deleting/moving a non-existent file, the operation succeeds instead of failing, and any orphan vector index records are cleaned up.

This follows industry standards:

• Linux rm -f - ignores nonexistent files
• AWS S3 DeleteObject - returns success for non-existent keys
• Kubernetes DELETE API - idempotent by design

Related Issue

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test update

Changes Made

• AGFS Server (Go): Fixed HTTP status code for non-existent files

  • Changed fmt.Errorf("no such file...") to filesystem.NewNotFoundError() so mapErrorToStatus() returns 404 instead of 500
  • Affected plugins: localfs, memfs, queuefs, serverinfofs

• AGFS SDK (Python): Added force parameter to rm() method

  • Defaults to force=True (like rm -f)
  • 404 responses return success {"message": "deleted"} instead of raising exception
  • Introduced AGFSHTTPError with status_code attribute for better error handling

• VikingFS: Idempotent rm() and mv() with vector index cleanup

  • rm(): Deleting non-existent file succeeds and cleans any orphan index records
  • mv(): When source not found (404), cleans all related URIs from vector index

Testing

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have tested this on the following platforms:
  • Linux
  • macOS
  • Windows

Checklist

• My code follows the project's coding style
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Screenshots (if applicable)

N/A

Additional Notes

Before (500 error for non-existent file):

Server returned 500 Internal Server Error with message "no such file or directory"

VikingFS.rm(uri)
    │
    ▼
AGFS SDK: rm(path)
    │
    ▼
HTTP DELETE /files?path=xxx
    │
    ▼
localfs.Remove(path)
    │
    ▼
return fmt.Errorf("no such file or directory: %s", path)
    │
    ▼
Handler: status := mapErrorToStatus(err)
    │
    ▼
errors.Is(err, filesystem.ErrNotFound)  ──► false (普通 error 没有 Is() 方法)
    │
    ▼
return http.StatusInternalServerError (500)
    │
    ▼
AGFS SDK: raise AGFSClientError("no such file...")
    │
    ▼
VikingFS: ❌ Exception 抛出，向量索引未清理

After (graceful success):

Deleting non-existent file succeeds silently and returns {"message": "deleted"}

VikingFS.rm(uri)
    │
    ▼
AGFS SDK: rm(path, force=True)
    │
    ▼
HTTP DELETE /files?path=xxx
    │
    ▼
localfs.Remove(path)
    │
    ▼
return filesystem.NewNotFoundError("remove", path)
    │
    ▼
Handler: status := mapErrorToStatus(err)
    │
    ▼
errors.Is(err, filesystem.ErrNotFound)  ──► true (NotFoundError 实现了 Is() 方法)
    │
    ▼
return http.StatusNotFound (404)
    │
    ▼
AGFS SDK: force=True && status_code=404  ──► return {"message": "deleted"}
    │
    ▼
VikingFS: _delete_from_vector_store()  ──► 清理孤儿索引
    │
    ▼
✅ Success

Why Idempotent Delete Matters

In distributed systems and concurrent environments, idempotent operations are crucial for:

1. Retry Safety - Retrying failed requests won't cause errors
2. Race Condition Handling - Multiple delete requests for same file all succeed
3. Index Consistency - Orphan vector index records get cleaned even if file already deleted

[qin-ctx]

这里应该用 openstream ？