fix(admin): avoid stale Telegram webhook alerts

Only surface Telegram delivery errors while updates are still pending, and register the webhook after the aiohttp webhook site starts listening.

tests/test_admin_config_health.py

@@ -239,16 +239,26 @@ class TelegramAlertsTests(unittest.IsolatedAsyncioTestCase):
         alerts = await health.telegram_alerts(bot, _settings())
         self.assertEqual(_alert_ids(alerts), ["telegram_webhook_mismatch"])
 
-    async def test_recent_delivery_error_reported(self):
+    async def test_recent_delivery_error_with_pending_update_reported(self):
         info = self._webhook_info(
             last_error_date=datetime.now(timezone.utc),
             last_error_message="SSL error",
+            pending_update_count=1,
         )
         bot = SimpleNamespace(get_webhook_info=AsyncMock(return_value=info))
         alerts = await health.telegram_alerts(bot, _settings())
         self.assertEqual(_alert_ids(alerts), ["telegram_webhook_error"])
         self.assertEqual(alerts[0].params["error"], "SSL error")
 
+    async def test_recent_delivery_error_without_pending_update_not_reported(self):
+        info = self._webhook_info(
+            last_error_date=datetime.now(timezone.utc),
+            last_error_message="Connection refused",
+            pending_update_count=0,
+        )
+        bot = SimpleNamespace(get_webhook_info=AsyncMock(return_value=info))
+        self.assertEqual(await health.telegram_alerts(bot, _settings()), [])
+
     async def test_stale_delivery_error_not_reported(self):
         info = self._webhook_info(last_error_date=time.time() - 7200)
         bot = SimpleNamespace(get_webhook_info=AsyncMock(return_value=info))

tests/test_main_bot_startup.py

@@ -45,6 +45,29 @@ def test_worker_starts_backup_task_without_enabled_guard():
     assert guarded_backup_tasks == []
 
 
+def test_telegram_webhook_configuration_is_deferred_until_site_start():
+    main_source = Path("backend/bot/main_bot.py").read_text(encoding="utf-8")
+    web_source = Path("backend/bot/app/web/web_server.py").read_text(encoding="utf-8")
+    tree = ast.parse(main_source)
+    startup_node = next(
+        node
+        for node in ast.walk(tree)
+        if isinstance(node, ast.AsyncFunctionDef) and node.name == "on_startup_configured"
+    )
+
+    startup_set_webhook_calls = [
+        node
+        for node in ast.walk(startup_node)
+        if isinstance(node, ast.Attribute) and node.attr == "set_webhook"
+    ]
+
+    assert startup_set_webhook_calls == []
+    assert "after_webhooks_started=_after_webhooks_started" in main_source
+    assert web_source.index("await site.start()") < web_source.index(
+        "await after_webhooks_started()"
+    )
+
+
 def test_telegram_startup_network_error_retries_until_success_without_traceback(caplog):
     calls = []