chore: 更新python版本到3.13和pyflowx到0.2.0，简化json响应代码

调整了emlmanager.py里的json响应代码格式，让代码更简洁

.python-version

@@ -1 +1 @@
-3.8
+3.13

src/pyflowx/cli/emlmanager.py

@@ -557,15 +557,13 @@ class EmlManagerHandler(BaseHTTPRequestHandler):
 
         emails = self.db.search_emails(keyword, field, limit, offset)
         total_count = self.db.get_email_count()
-        self._send_json_response(
+        self._send_json_response({
-            {
             "emails": emails,
             "count": len(emails),
             "total": total_count,
             "limit": limit,
             "offset": offset,
-            }
+        })
-        )
 
     def _api_get_email(self, query_params: dict[str, list[str]]) -> None:
         """API: 获取单个邮件详情."""

uv.lock

@@ -2184,7 +2184,7 @@ wheels = [
 
 [[package]]
 name = "pyflowx"
-version = "0.1.13"
+version = "0.2.0"
 source = { editable = "." }
 dependencies = [
     { name = "graphlib-backport", marker = "python_full_version < '3.9'" },