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.

frontend/.dockerignore

@@ -0,0 +1,6 @@
+node_modules/
+dist/
+.vite/
+*.log
+.DS_Store
+.git/