feat(ops): launchd jobs (nightly + market-open) + caffeinate + install scripts

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016DvdRZkyCy9NJpHYDdPqmS

scripts/execute.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+# launchd wrapper for the market-open execution (08:30 CT = 09:30 ET). Gated on Alpaca's clock.
+cd /Users/aryan/Documents/GitHub/trading-agent
+export PATH="/opt/homebrew/bin:$PATH"
+mkdir -p state/logs
+exec uv run python -m execution.run_market_open >> state/logs/launchd_execution.log 2>&1