Bug 1 improvement: Replaced double API call pattern (sync + update_remnawave_user)
with single _sync_subscription_to_panel call that accepts reset_traffic parameter.
This prevents TRIAL status being overwritten to EXPIRED by the second call's
different status computation logic.
Bug 2 improvement: Moved keyboard construction inside try block to prevent
AttributeError crash if locale keys are missing. Switched button text from
attribute access (texts.KEY) to defensive texts.get('KEY', fallback).
Added empty template guard to prevent sending empty messages to Telegram API.
Fringg
b2cf4aaa91