Surface {{groupNow.*}} template variables (title, note, colour, times,
custom fields) in the automation template autocomplete so events inside a
group can reference their group. The runtime store already carries
groupNow, so substitution and filters worked already; this makes it
discoverable.
Extend the message-secondary action with an optional text field so an
automation can set the secondary message content, not just its source.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LZYPZVdZLWowU7DyzGkWyy
* refactor: runtime types
* refactor: runtimeState functions to use the split type
* refactor: RuntimeService to use the new split data
* refactor: use the split data in the UI
* update comments
* refactor: rename runtime to offset
* fix utils test