Fix engine daemon exit and UI DuckDB access

- Add if __name__ == '__main__' guard to main.py (engine exited immediately)
- Update Dockerfile TA-Lib build for ARM64 (config.guess/config.sub)
- Add redis dependency to pyproject.toml
- Add docker-compose.override.yml for local dev with source mounting
- Remove :ro from UI engine volume mount (DuckDB needs write for WAL)

pyproject.toml

@@ -58,6 +58,9 @@ dependencies = [
     "structlog>=24.1.0",
     "rich>=13.7.0",
     
+    # Redis
+    "redis>=5.0.0",
+
     # HTTP client
     "httpx>=0.26.0",
 ]