Problem

The keepalive loop introduced in d42ef2a (v2026.2.24, #25886) continuously refreshes Signal's typing indicator every ~3s. Without a stop callback, fireStop() only halts the JS interval — no 'stop typing' API call is ever sent. Signal's indicator then persists until its own TTL expires, but that TTL kept getting reset by the keepalive, causing the perpetual typing indicator regression reported in #26891.

Fix

Wire up the stop callback in createTypingCallbacks for the Signal channel using sendTypingSignal with { stop: true }. This explicitly clears the indicator when the response completes or NO_REPLY is returned.

stop: async () => {
  if (!ctxPayload.To) return;
  await sendTypingSignal(ctxPayload.To, {
    baseUrl: deps.baseUrl,
    account: deps.account,
    accountId: deps.accountId,
    stop: true,
  });
},

sendTypingSignal already supported { stop: true } — it just wasn't wired up for Signal.

Notes

• Telegram has the same missing stop callback (refs [Bug]: Telegram typing indicator persists indefinitely after response completes #26761, v2026.2.24 regression: Telegram typing indicator stays active after response completes #26841) — separate fix warranted there
• Tested locally on Signal with claude-sonnet-4-6, both short and long responses, and NO_REPLY turns

Closes #26891

Greptile Summary

Added stop callback to Signal's typing indicator implementation to properly clear the typing indicator when responses complete or NO_REPLY is returned.

• Wired up the stop callback in createTypingCallbacks for the Signal channel
• Calls sendTypingSignal with { stop: true } to explicitly clear the indicator
• Mirrors the structure of the existing start callback with proper guard clause for missing ctxPayload.To

The fix directly addresses the perpetual typing indicator regression where the keepalive loop continuously refreshed the indicator without ever sending a stop signal. The sendTypingSignal function already supported the stop parameter - it just wasn't being used.

Confidence Score: 5/5

• This PR is safe to merge with minimal risk
• Score reflects a straightforward bug fix that follows existing patterns. The implementation correctly wires up the stop callback using an API that already supported this functionality. The code structure mirrors the start callback, includes proper guard clauses, and directly addresses the reported issue with no behavioral side effects.
• No files require special attention

_{Last reviewed commit: 4b0b120}

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