Add ETHUSDT liquidity monitor with control scripts and .gitignore

[FD3RF]

Motivation

• Provide a lightweight monitor that scans 15m Binance Futures candles for liquidity sweeps and sends alerts for potential reversal opportunities.
• Add simple process management scripts and useful ignores for running the monitor in the background and capturing logs.

Description

• Add liquidity_monitor.py which fetches Binance futures klines, computes indicators (calculate_rsi, calculate_parabolic_sar), evaluates liquidity-sweep conditions in liquidity_signal, and dispatches alerts via Bark and Telegram.
• Implement a resilient polling loop in run_monitor with a --once option, cooldown handling, and helper functions fetch_futures_klines, get_request_session, and next_close_after.
• Add shell scripts scripts/start_monitor.sh, scripts/status_monitor.sh, and scripts/stop_monitor.sh to manage the background process and log/pid files.
• Add a .gitignore to exclude Python caches, compiled files, and log/pid files.

Testing

• No automated tests were executed for this change.

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Codex Task