iLink context_token has a limited TTL. When no user message has arrived
for an extended period (e.g. overnight), cron-initiated pushes fail with
errcode -14 (session timeout).
Tested that iLink accepts sends without context_token as a degraded
fallback, so we now automatically strip the expired token and retry
once. This keeps scheduled push messages (weather, digests, etc.)
working reliably without requiring a user message to refresh the
session first.
Changes:
- _send_text_chunk() catches iLinkDeliveryError with session-expired
errcode (-14) and retries without context_token
- Stale tokens are cleared from ContextTokenStore on session expiry
- All 34 existing weixin tests pass
e105b7ac93