Feature/delta team/epic r04 (#7)

## Summary

epic r04 - begin refactor

## Change Type

- [x] Cowork feature
- [ ] Bug fix
- [ ] Core AI contribution
- [ ] Test / hardening
- [ ] Performance
- [ ] Documentation

## Related Work

Cowork Task:

Core Repo: http://34.143.229.138/gitea-admin/fsg-ai-core-assets

Core AI Issue:

Core Task:

Related PR:

## Scope

What is intentionally included?

What is intentionally NOT included?

## Validation

- [ ] Unit tests
- [ ] Integration tests
- [ ] Manual verification
- [ ] Regression check

Commands / evidence:

## Security Impact

Permission / credential / network / customer data impact:

## Compatibility

- [ ] No breaking change
- [ ] Breaking change documented

## Reviewer Notes

Anything Cowork reviewers should pay attention to.

---------

Co-authored-by: Anh Tran Nguyen Minh <anhtnm1@fpt.com>
Co-authored-by: Huong Le Thi Thien <huongltt35@fpt.com>
Co-authored-by: Nam Pham Dinh Thanh <nampdt@fpt.com>
Co-authored-by: Vu Dam Tuan <vudt15@fpt.com>
Co-authored-by: Hiep Ha Van <hiephv3@fpt.com>
Co-authored-by: Lam Hoang Van <lamhv7@fpt.com>
Reviewed-on: #7
Co-authored-by: Duy Le Huu <duylh19@fpt.com>

core/ms365_local.py

@@ -28,10 +28,12 @@ _PREFIX = "ms365_local"
 
 
 def _roots() -> List[Path]:
+    """Mọi thư mục OneDrive tìm thấy trên máy."""
     return paths.detect_onedrive_roots()
 
 
 def _primary_root() -> Optional[Path]:
+    """Thư mục OneDrive chính; ``None`` nếu không có."""
     return paths.primary_onedrive_root()
 
 
@@ -45,6 +47,7 @@ def _resolve_under(root: Path, rel: str) -> Path:
 
 
 def _list_dir(base: Path, rel: str) -> dict:
+    """Liệt kê nội dung một thư mục con của OneDrive, chặn thoát ra ngoài gốc."""
     target = _resolve_under(base, rel)
     if not target.exists():
         raise FileNotFoundError(f"Not found: {rel or '.'}")
@@ -60,6 +63,7 @@ def _list_dir(base: Path, rel: str) -> dict:
 
 
 def _read_file(base: Path, rel: str) -> str:
+    """Đọc một tệp trong OneDrive dưới dạng văn bản, chặn thoát ra ngoài gốc."""
     target = _resolve_under(base, rel)
     if not target.is_file():
         raise FileNotFoundError(f"Not a file: {rel}")
@@ -68,6 +72,7 @@ def _read_file(base: Path, rel: str) -> str:
 
 
 def _write_file(base: Path, rel: str, content: str) -> dict:
+    """Ghi một tệp trong OneDrive, tự tạo thư mục cha, chặn thoát ra ngoài gốc."""
     target = _resolve_under(base, rel)
     target.parent.mkdir(parents=True, exist_ok=True)
     target.write_text(content or "", encoding="utf-8")
@@ -125,6 +130,9 @@ def build_ms365_local_tools(config) -> Tuple[List[ToolSpec], Optional[Callable[[
         ]
 
     def executor(name: str, args: dict) -> dict:
+        """Bộ thực thi tool MS365 cục bộ (đọc/ghi thẳng thư mục OneDrive đồng bộ trên
+        máy, không cần đăng nhập Graph), ghi nhật ký kiểm toán cho mỗi lần gọi.
+        """
         ok = False
         detail = ""
         try: