fix(issue summary): Close database connections after issue summary generation (#97555)

Fixes
[SENTRY-4BWM](https://sentry.io/organizations/sentry/issues/6793787515/).
The issue was that: ThreadPoolExecutor's new threads request database
connections, exhausting PostgreSQL's max_client_conn due to unreleased
connections.

- Wraps the `get_issue_summary` function call in a thread with a
function `_get_issue_summary_with_cleanup` to ensure database
connections are closed after the thread execution.
- This prevents connection leaks when running in a thread.


This fix was generated by Seer in Sentry, triggered by Rohan Agarwal. 👁️
Run ID: 734760

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Seer.](https://sentry.io/organizations/sentry/issues/6793787515/?seerDrawer=true)

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Co-authored-by: seer-by-sentry[bot] <157164994+seer-by-sentry[bot]@users.noreply.github.com>
Co-authored-by: getsantry[bot] <66042841+getsantry[bot]@users.noreply.github.com>

Author: 2 people

src/sentry/integrations/utils/issue_summary_for_alerts.py

@@ -3,6 +3,7 @@
 from typing import Any
 
 import sentry_sdk
+from django.db import close_old_connections
 
 from sentry import features, options
 from sentry.issues.grouptype import GroupCategory
@@ -15,6 +16,19 @@
 logger = logging.getLogger(__name__)
 
 
+def _get_issue_summary_with_cleanup(
+    group: Group, source: SeerAutomationSource
+) -> tuple[dict[str, Any], int]:
+    """
+    Wrapper for get_issue_summary that ensures database connections are properly closed.
+    This is needed when running in a thread to prevent connection leaks.
+    """
+    try:
+        return get_issue_summary(group, source=source)
+    finally:
+        close_old_connections()
+
+
 def fetch_issue_summary(group: Group) -> dict[str, Any] | None:
     """
     Try to fetch an issue summary with a timeout of 5 seconds.
@@ -52,7 +66,7 @@ def fetch_issue_summary(group: Group) -> dict[str, Any] | None:
         with sentry_sdk.start_span(op="ai_summary.fetch_issue_summary_for_alert"):
             with concurrent.futures.ThreadPoolExecutor() as executor:
                 future = executor.submit(
-                    get_issue_summary, group, source=SeerAutomationSource.ALERT
+                    _get_issue_summary_with_cleanup, group, SeerAutomationSource.ALERT
                 )
                 summary_result, status_code = future.result(timeout=timeout)