Implement custom Telegram notification templates #2
Description
In a future stage, the Telegram notifier may be extended to support:
YAML-defined templates
per-module overrides
per-event / per-error-type overrides
fallback hierarchy:
module-specific event template
event-type template
level template
default template
This must remain compatible with the current notifier simplicity and should only be introduced when the current Bash template model becomes too limiting.