Backport from v6 (88d5865a8). Recovery webhook notifications were using
the firing PayloadTemplate which services like Telegram, Teams, Discord
etc. silently rejected as malformed. Now uses a three-tier template
pipeline matching the firing path:
- Tier 1: Custom user template (if configured)
- Tier 2: Service-specific ResolvedPayloadTemplate (Discord green embed,
Telegram chat_id+text, Slack header blocks, Teams MessageCard/Adaptive,
PagerDuty event_action:"resolve", Pushover, Gotify, Mattermost)
- Tier 3: Generic JSON fallback (backward compatible)
Also adds Event, ResolvedAt, ResolvedAtISO fields to WebhookPayloadData.
rcourtman
77bd2e70d9