Initial commit — options pricing dashboard

Full-stack options analytics app: IV surface, Greeks, skew metrics,
vol term structure. Yahoo Finance data with Black-Scholes IV computation
and historical vol fallback for after-hours data.

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

.gitignore

@@ -0,0 +1,8 @@
+node_modules/
+backend/data/*.db
+backend/data/*.db-shm
+backend/data/*.db-wal
+backend/.env
+dist/
+*.log
+.DS_Store