{{note}} renders empty in webhook bodies when an alert fires #3644

What happened?

{{note}} is empty in Generic and incident.io webhook bodies when an alert fires, even when the alert has a note. "Send test" does show a note, so the template looks right until a real alert fires.

The path, at current main:

• fireChannelEvent builds the template view's alert as an object literal, and note is not one of its fields (checkAlerts/index.ts#L538-L565).
• renderAlertTemplate reads note: alert.note ?? '' from that view, so it is always '' (template.ts#L770).
• The Generic transport writes message.note into {{note}} (generic.ts#L105).
• The test webhook builds its message with a hard-coded note, so it never takes this path (webhooks.ts#L517).

I found this reading the source and haven't triggered it on a running instance.

Steps to reproduce

Reproduces on play.hyperdx.io? didn't try

From the code above, this should show it:

1. Create an alert with a note, on a Generic webhook whose body includes {"note": "{{note}}"}.
2. Click "Send test": the receiver gets the sample note.
3. Let the alert fire: the receiver gets "note": "".

How are you running HyperDX?

Self-hosted app image with our own ClickHouse and the standalone collector. The code above is current main.

Where does it show up?

The API: webhook delivery from the alert worker.

Debug info

N/A, not a UI bug.

Logs

N/A.

The fix looks like one line, note: alert.note, in that literal, plus a test that renders {{note}} through the worker path. I'd be glad to send it if this is marked Accepting PR.