feat(phase-0): scaffold backend + web + docker + DB schema

- docker-compose.yml: timescaledb-ha (timescaledb 2.27 + vectorscale + pgvector + pgai)
  + backend (FastAPI, CUDA 12.1) + web (Next.js 14)
- docker-compose.gpu.yml: GPU profile overlay for RTX 3070 Ti
- build.bat: Windows bootstrap, auto-detects nvidia-smi and selects GPU/CPU compose
- backend: Dockerfile, pyproject.toml, FastAPI skeleton with /health and /health/db
- DB migration 001_init.sql: symbols (with trigram search), ohlcv_daily/1m (hypertables),
  macro_daily, trading_value_daily, news (vector embedding), predictions
  (with user_triggered flag for on-demand UX), prediction_outcomes, model_performance
- web: Next.js 14 + Tailwind + lightweight-charts placeholder
- README: KIS/DART/HuggingFace token issuance guides + 10 seed tickers + run instructions

web/postcss.config.js

@@ -0,0 +1,3 @@
+module.exports = {
+  plugins: { tailwindcss: {}, autoprefixer: {} },
+};