Crypto trading bot: engine, brokers, backtester, dashboard, deploy

FastAPI backend with a single-strategy async engine, paper and Binance
brokers, pure-python indicators, a backtester that shares the engine's
portfolio math, and a Vue dashboard with a live WebSocket feed. Adds the
Gitea Actions CI/CD workflow that deploys to Traefik via docker_default.

backend/requirements.txt

@@ -0,0 +1,11 @@
+# Core web stack
+fastapi>=0.115
+uvicorn>=0.34
+pydantic>=2.9
+pydantic-settings>=2.7
+# Persistence (sync SQLAlchemy; SQLite by default, Postgres optional)
+SQLAlchemy>=2.0.36
+# HTTP client used for market data + live exchange REST calls
+httpx>=0.28
+# WebSocket protocol support for uvicorn / starlette
+websockets>=14.0