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/routers/positions.py

@@ -0,0 +1,78 @@
+from datetime import datetime
+from fastapi import APIRouter, Depends, Header, HTTPException, Query
+from sqlalchemy.orm import Session
+
+from app.database import get_db
+from app.models.db_models import Device, OptionPosition
+from app.models.schemas import OptionPositionCreate, OptionPositionClose, OptionPositionResponse
+
+router = APIRouter(prefix="/positions", tags=["positions"])
+
+
+def _get_device(x_device_token: str = Header(...), db: Session = Depends(get_db)) -> Device:
+    device = db.query(Device).filter(Device.apns_token == x_device_token).first()
+    if not device:
+        raise HTTPException(status_code=404, detail="Device not registered.")
+    return device
+
+
+@router.get("", response_model=list[OptionPositionResponse])
+def get_positions(
+    status: str | None = Query(None),
+    device: Device = Depends(_get_device),
+    db: Session = Depends(get_db),
+):
+    query = db.query(OptionPosition).filter(OptionPosition.device_id == device.id)
+    if status:
+        query = query.filter(OptionPosition.status == status)
+    return query.order_by(OptionPosition.opened_at.desc()).all()
+
+
+@router.post("", response_model=OptionPositionResponse, status_code=201)
+def log_position(
+    body: OptionPositionCreate,
+    device: Device = Depends(_get_device),
+    db: Session = Depends(get_db),
+):
+    position = OptionPosition(
+        device_id=device.id,
+        ticker=body.ticker,
+        strategy=body.strategy,
+        strike=body.strike,
+        expiration=body.expiration,
+        premium_received=body.premium_received,
+        contracts=body.contracts,
+        status="open",
+    )
+    db.add(position)
+    db.commit()
+    db.refresh(position)
+    return position
+
+
+@router.patch("/{position_id}", response_model=OptionPositionResponse)
+def close_position(
+    position_id: int,
+    body: OptionPositionClose,
+    device: Device = Depends(_get_device),
+    db: Session = Depends(get_db),
+):
+    position = (
+        db.query(OptionPosition)
+        .filter(OptionPosition.id == position_id, OptionPosition.device_id == device.id)
+        .first()
+    )
+    if not position:
+        raise HTTPException(status_code=404, detail="Position not found.")
+
+    valid_statuses = ("closed", "rolled")
+    if body.status not in valid_statuses:
+        raise HTTPException(status_code=422, detail=f"status must be one of {valid_statuses}")
+
+    position.status = body.status
+    position.close_reason = body.close_reason
+    position.closed_at = datetime.utcnow()
+
+    db.commit()
+    db.refresh(position)
+    return position