Initial implementation of Options Sidekick

Full-stack iOS options trading assistant:
- Python FastAPI backend with SQLite, APScheduler (15-min position monitor),
  APNs push notifications, and yfinance market data integration
- Signal engine: IV Rank (rolling HV proxy), SMA-50/200, swing-based
  support/resistance, earnings detection, signal strength scoring and
  noise-resistant SHA hash for change detection
- Recommendation engine: covered call and cash-secured put strike/expiry
  selection across 0DTE, 1DTE, weekly, and monthly horizons
- REST API: /devices, /portfolio, /recommendations, /positions, /signals, /alerts
- iOS SwiftUI app (iOS 17+): dashboard, recommendations, trades, portfolio,
  and alerts tabs with push notification deep-linking
- Unit + integration tests for signal engine and API layer

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

backend/app/config.py

@@ -0,0 +1,19 @@
+from pydantic_settings import BaseSettings
+
+
+class Settings(BaseSettings):
+    database_url: str = "sqlite:///./app.db"
+    apns_key_path: str = "./AuthKey_XXXXXXXXXX.p8"
+    apns_key_id: str = ""
+    apns_team_id: str = ""
+    apns_bundle_id: str = "com.yourname.options-sidekick"
+    apns_use_sandbox: bool = True
+    recommendation_throttle_minutes: int = 5
+    monitor_interval_seconds: int = 900  # 15 minutes
+
+    class Config:
+        env_file = ".env"
+        env_file_encoding = "utf-8"
+
+
+settings = Settings()