Feat: add SMTP support for user invitation emails (#9479)

### What problem does this PR solve?

Add SMTP support for user invitation emails

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

api/apps/tenant_app.py

@@ -18,12 +18,14 @@ from flask import request
 from flask_login import login_required, current_user
 
 from api import settings
+from api.apps import smtp_mail_server
 from api.db import UserTenantRole, StatusEnum
 from api.db.db_models import UserTenant
 from api.db.services.user_service import UserTenantService, UserService
 
 from api.utils import get_uuid, delta_seconds
 from api.utils.api_utils import get_json_result, validate_request, server_error_response, get_data_error_result
+from api.utils.web_utils import send_invite_email
 
 
 @manager.route("/<tenant_id>/user/list", methods=["GET"])  # noqa: F821
@@ -78,6 +80,20 @@ def create(tenant_id):
         role=UserTenantRole.INVITE,
         status=StatusEnum.VALID.value)
 
+    if smtp_mail_server and settings.SMTP_CONF:
+        from threading import Thread
+
+        user_name = ""
+        _, user = UserService.get_by_id(current_user.id)
+        if user:
+            user_name = user.nickname
+
+        Thread(
+            target=send_invite_email,
+            args=(invite_user_email, settings.MAIL_FRONTEND_URL, tenant_id, user_name or current_user.email),
+            daemon=True
+        ).start()
+
     usr = invite_users[0].to_dict()
     usr = {k: v for k, v in usr.items() if k in ["id", "avatar", "email", "nickname"]}