Initial commit: MyMidas personal finance tracker

Full-stack self-hosted finance app with FastAPI backend and React frontend.

Features:
- Accounts, transactions, budgets, investments with GBP base currency
- CSV import with auto-detection for 10 UK bank formats
- ML predictions: spending forecast, net worth projection, Monte Carlo
- 7 selectable themes (Obsidian, Arctic, Midnight, Vault, Terminal, Synthwave, Ledger)
- Receipt/document attachments on transactions (JPEG, PNG, WebP, PDF)
- AES-256-GCM field encryption, RS256 JWT, TOTP 2FA, RLS, audit log
- Encrypted nightly backups + key rotation script
- Mobile-responsive layout with bottom nav

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

backend/app/core/rate_limiter.py

@@ -0,0 +1,28 @@
+"""
+Redis sliding window rate limiter.
+"""
+import time
+from redis.asyncio import Redis
+
+
+async def is_rate_limited(
+    redis: Redis,
+    key: str,
+    limit: int,
+    window_seconds: int = 60,
+) -> tuple[bool, int]:
+    """
+    Returns (is_limited, requests_remaining).
+    Uses a sorted set with timestamps as scores for sliding window.
+    """
+    now = time.time()
+    window_start = now - window_seconds
+    pipe = redis.pipeline()
+    pipe.zremrangebyscore(key, 0, window_start)
+    pipe.zadd(key, {str(now): now})
+    pipe.zcard(key)
+    pipe.expire(key, window_seconds + 1)
+    results = await pipe.execute()
+    count = results[2]
+    remaining = max(0, limit - count)
+    return count > limit, remaining