Function wake_text_for 

pub fn wake_text_for(
    task: &SessionTask,
    transition: TaskTransition,
) -> Option<String>

Render the wake text for a task transition under the task’s wake_policy.

Returns None when the policy does not wake on this transition (so the caller enqueues nothing). This encodes the same gating the between-turn waker uses (DbSessionTaskRegistry::maybe_wake_*) so mid-turn and between-turn delivery agree on when a wake fires:

• Silent — never.
• OnTerminal — only on a terminal transition.
• OnActivity — terminal, awaiting_input, and outbound messages.

The text is rendered purely from the task snapshot: the terminal summary / result path, the awaiting-input prompt, or the latest progress / detail for a message. The full message thread stays in the task record; the wake tells the agent to look.