feat: Add GitHub username retrieval function

- Implement `get_github_username()` to fetch GitHub username via API
- Update `get_selected_issue_ids()` to use GitHub username instead of git username
- Enhance GitHub issue selection workflow with authenticated username retrieval

merico/github/commit/commit.py

@@ -13,9 +13,9 @@ sys.path.append(os.path.join(os.path.dirname(os.path.abspath(__file__)), ".."))
 
 from common_util import assert_exit  # noqa: E402
 from git_api import (
-    get_git_username,
     get_github_repo,
     get_github_repo_issues,
+    get_github_username,
     get_issue_info,
     subprocess_check_output,
     subprocess_run,
@@ -433,9 +433,7 @@ def get_selected_issue_ids():
     Returns:
         list: 用户选中的issue id列表
     """
-    name = get_git_username()
-    if not name:
-        return
+    name = get_github_username()
     issue_repo = get_github_repo(True)
     issues = get_github_repo_issues(issue_repo, assignee=name, state="open")
     if issues:

merico/github/git_api.py

@@ -538,8 +538,14 @@ def save_last_base_branch(base_branch=None):
     save_config_item(project_config_path, "last_base_branch", base_branch)
 
 
-def get_git_username():
-    return subprocess_check_output(["git", "config", "--get", "user.name"]).decode("utf-8").strip()
+def get_github_username():
+    url = f"{GITHUB_API_URL}/user"
+    headers = {
+        "Authorization": f"token {GITHUB_ACCESS_TOKEN}",
+        "Accept": "application/vnd.github.v3+json",
+    }
+    response = requests.get(url, headers=headers)
+    return response.json()["login"]
 
 
 def get_github_repo_issues(