Introduces telegram_bot.py: python-telegram-bot v20+ async bot that
presents a persistent Scan Signal inline button. Each press fetches a
live USD/JPY signal via SignalAggregator and formats it with emoji,
MTF breakdown, top bull/bear reasons, and warnings. STRONG_BUY /
STRONG_SELL signals additionally render the full trade setup (entry,
SL, TP1, TP2, RR). Adds python-telegram-bot>=20.0 to requirements.txt.
data_provider now uses TDClient.time_series().as_pandas() instead of
hand-rolled REST calls. Throttle, validation, and parquet caching are
unchanged. Adds twelvedata>=1.2.0 to requirements.txt.
Harwinder