chore: initial project scaffold for quant trading learning

Sets up project structure with yfinance-based OHLCV fetcher for top
100 S&P companies, Jupyter notebook scaffold, and uv-managed deps.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -0,0 +1,51 @@
+[project]
+name = "learn-trading"
+version = "0.0.1"
+description = "Combined trading research environment"
+readme = "README.md"
+requires-python = ">=3.12"
+dependencies = [
+    "marimo>=0.23.2",
+    "arch>=8.0.0",
+    "backtesting>=0.6.5",
+    "backtrader>=1.9.78.123",
+    "ccxt>=4.5.50",
+    "empyrical-reloaded>=0.5.12",
+    "finta>=1.3",
+    "hmmlearn>=0.3.3",
+    "jupyterlab>=4.5.6",
+    "lightgbm>=4.6.0",
+    "lxml>=6.1.0",
+    "matplotlib>=3.10.8",
+    "mplfinance>=0.12.10b0",
+    "numpy>=2.2.6,<2.3",
+    "pandas>=2.3.3",
+    "pandas-ta>=0.4.71b0",
+    "plotly>=6.7.0",
+    "polars>=1.40.1",
+    "pyarrow>=24.0.0",
+    "pyportfolioopt>=1.6.0",
+    "qlib>=0.0.2.dev20",
+    "quantstats>=0.0.81",
+    "riskfolio-lib>=7.2.1",
+    "scikit-learn>=1.7.2",
+    "scipy>=1.17.1",
+    "sktime>=0.40.1",
+    "statsmodels>=0.14.6",
+    "ta>=0.11.0",
+    "ta-lib>=0.6.8",
+    "torch>=2.0.0",
+    "transformers>=4.0.0",
+    "tscv>=0.1.3",
+    "vectorbt>=1.0.0",
+    "xgboost>=3.2.0",
+    "yfinance>=1.3.0",
+]
+
+[[tool.uv.index]]
+name = "pytorch-cpu"
+url = "https://download.pytorch.org/whl/cpu"
+explicit = true
+
+[tool.uv.sources]
+torch = { index = "pytorch-cpu" }