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/jira_tool.py

@@ -20,11 +20,13 @@ _KEY_RE = re.compile(r"\b([A-Z][A-Z0-9]+-\d+)\b")
 
 
 def _conf(config: Dict[str, Any] | None) -> Dict[str, str]:
+    """Ba trường cấu hình Jira đã cắt khoảng trắng: base_url, email, api_token."""
     return {k: str((config or {}).get(k, "") or "").strip()
             for k in ("base_url", "email", "api_token")}
 
 
 def configured(config: Dict[str, Any] | None) -> bool:
+    """Đã cấu hình đủ ba trường để gọi Jira chưa."""
     c = _conf(config)
     return bool(c["base_url"] and c["email"] and c["api_token"])
 
@@ -82,6 +84,7 @@ def get_issue_by_url(config: Dict[str, Any] | None, url: str) -> str:
 
 
 def _get(config: Dict[str, Any], path: str, params: dict = None):
+    """Gọi Jira REST API bằng xác thực cơ bản, qua lớp TLS có ghim chứng chỉ nội bộ."""
     from . import tls_trust
 
     c = _conf(config)
@@ -97,6 +100,7 @@ def _get(config: Dict[str, Any], path: str, params: dict = None):
 
 
 def _fmt_issue(it: dict) -> str:
+    """Một dòng tóm tắt issue: mã, trạng thái và tiêu đề."""
     f = it.get("fields", {}) or {}
     status = (f.get("status") or {}).get("name", "?")
     assignee = (f.get("assignee") or {}).get("displayName", "unassigned")