* fix(telegram): clear send_path_degraded on successful reconnect
_send_path_degraded was cleared only in _verify_polling_after_reconnect,
60s after reconnect and only if scheduled. A clean start_polling() reconnect
left the flag stuck True, short-circuiting send() and blocking all outbound
messages until the deferred probe ran (or forever if it never did).
Clear the flag the moment start_polling() succeeds — that is the recovery
signal. The deferred probe remains a defensive re-check that re-enters the
reconnect ladder (re-setting the flag) if it detects a silent wedge.
Fixes#35205.
* docs: add infographic for #35205 telegram send-path fix
2ecb6f7fe6