Enhance Python Trading Bots Infrastructure

PHP, Python, Software Architecture, Software Testing, C++ Programming, Software Development, API, Financial APIs · Python Dev — Harden Live OANDA/Schwab Trading Bot Infrastructure (No Strategy Work) Description: We run two Python trading bots: one on OANDA (FX/CFD), one on Schwab (options). We need infrastructure fixes, NOT a new trading strategy — we already tested and rejected a breakout strategy against real historical data, so please don’t pitch indicators or “high win rate” ideas. Scope: 1. Asset lock (OANDA): Restrict the bot to a short instrument allow-list (e.g. NAS100_USD, SPX500_USD, EUR_USD), enforced at the order-request level, not just config. 2. Permanent trade log: Append-only CSV/SQLite logger recording every order decision (timestamp, instrument, reasoning, size, SL/TP, result) — must survive outside system journald, which currently loses history after ~32 hours. 3. Schwab options sizing fix: Refactor contract sizing to enforce a $500 minimum trade size (via ceiling math), $300 max per-contract ask, 5-contract cap, with up to $600 total overrun allowed. Include unit tests. 4. Defensive coding: Proper exception handling on all API calls, no silent failures, safe fallback states. Not in scope: Any change to entry/exit signal logic or new strategies. Any future strategy work will