fix[backend](email): added migrations with missing email configs

backend/migrations/000003_alert_notification_recipients.down.sql

@@ -0,0 +1,5 @@
+-- Remove the seeded alert/incident notification recipient config rows.
+DELETE FROM utm_configuration_parameter WHERE conf_param_short IN (
+    'utmstack.alerts.notification_to',
+    'utmstack.alerts.notification_cc'
+);

backend/migrations/000003_alert_notification_recipients.up.sql

@@ -0,0 +1,18 @@
+-- 000003_alert_notification_recipients.up.sql
+--
+-- Seed the two config rows that hold the global alert/incident email recipients.
+-- Both are optional, comma-separated lists. When both are empty the incident
+-- mailer falls back to every activated user (see modules/incidents mailer).
+--
+-- The appconfig usecase only UPDATEs pre-seeded rows, so these must exist for
+-- GET/PUT /config/<key> to work.
+INSERT INTO utm_configuration_parameter
+    (conf_param_short, conf_param_large, conf_param_description, conf_param_value, conf_param_required, conf_param_datatype, conf_param_option)
+SELECT v.conf_param_short, v.conf_param_large, v.conf_param_description, v.conf_param_value, v.conf_param_required, v.conf_param_datatype, v.conf_param_option
+FROM (VALUES
+    ('utmstack.alerts.notification_to', 'Alerts notification To',  'Comma-separated addresses that receive alert/incident notifications. Empty falls back to every activated user.', '', false, 'text', NULL),
+    ('utmstack.alerts.notification_cc', 'Alerts notification Cc',  'Comma-separated addresses copied on alert/incident notifications.',                                          '', false, 'text', NULL)
+) AS v(conf_param_short, conf_param_large, conf_param_description, conf_param_value, conf_param_required, conf_param_datatype, conf_param_option)
+WHERE NOT EXISTS (
+    SELECT 1 FROM utm_configuration_parameter c WHERE c.conf_param_short = v.conf_param_short
+);