pub fn interpolate(template: &str, payload: &Value) -> Result<String, String>Expand description
Substitute {{ dotted.path }} placeholders in a task template from payload.
The payload is data, not instruction. Whoever writes the automation
chooses where a webhook’s fields land in the prompt; the sender only fills
those slots. Values are truncated at MAX_SUBSTITUTION.
A path that is missing or null is an error naming that path — the run is
recorded as failed instead of spawning an agent on a half-formed prompt.