Alert centre and log level error codes (mpbx-alerts)

Raised by the alert routes (/api/v1/system/alerts, /api/v1/system/alert-settings) and the log level routes (/api/v1/system/log-levels; W7-OBS-01a). All of them need a system-scope credential. Messages never contain a webhook URL, a signing secret or an e-mail address. Guides: Alerts, Logging.

Code	Kind	Meaning	What to do
MPBX-ALERT-NOT-FOUND	not_found	No alert has that id (it was purged after 90 days, or the id is wrong).	List the alerts again.
MPBX-ALERT-SETTINGS-INVALID	invalid_argument	A setting is not acceptable; the message names the field: a recipient that is not a plain address (user@example.com, no display name, no list), more than 10 recipients, or a webhook_url the outbound guard refuses (not https, credentials in the URL, an internal name or address, a port below 1024 other than 443).	Fix the named field. A webhook must be a public https address.
MPBX-ALERT-SETTINGS-CONFLICT	conflict	The settings changed since the ETag you sent in If-Match.	Read them again and re-apply the change.
MPBX-ALERT-NO-CHANNEL	invalid_argument	A test notification was asked for, but no recipient and no webhook is configured.	Add a recipient or a webhook first.
MPBX-ALERT-LOG-LEVEL-INVALID	invalid_argument	The log filter is not level or comma-separated target=level pairs (levels error, warn, info, debug, trace, off; target names of letters, digits, _ and :), is longer than 512 characters, or ttl_minutes is not 1 to 1440. Span and field filters are refused.	Use for example debug, or info,mpbx_sip_core=debug.
MPBX-ALERT-SECRET-UNREADABLE	config	The stored webhook signing secret cannot be opened with this install's master key (a restored database with another master key).	Save the settings again with rotate_webhook_secret to make a new secret.