feat: add liquidity_sweep and price_action_reversal algorithms (#15, #16)

- Add detect_liquidity_levels() and detect_price_action_signal() to indicator_service.py
- Wire both algorithms into candle_service.py get_indicators()
- Add scoring logic and correlation groups in signal_scoring.py
- Add liquidity_sweep and price_action_reversal to STRATEGY_NAMES/DISPLAY in strategy.py
- Add funding_service.py for funding_oi algorithm (algorithm #14)
- Add rate_limiter.py for auth endpoints
- Fix: add slowapi==0.1.9 to Dockerfile
- Fix: get_db -> get_db_session in analytics.py
- Fix: remove from __future__ import annotations in auth.py

System now runs 16 algorithms: 13 original + funding_oi + liquidity_sweep + price_action_reversal

backend/app/schemas/strategy.py

@@ -7,7 +7,7 @@ from typing import Optional
 from pydantic import BaseModel
 
 
-# Available strategy names — full list of 13 voting algorithms
+# Available strategy names — full list of 16 voting algorithms
 STRATEGY_NAMES = [
     "double_bb_rsi",
     "macd_crossover",
@@ -22,6 +22,9 @@ STRATEGY_NAMES = [
     "mfi",
     "fvg",
     "candlestick",
+    "liquidity_sweep",
+    "price_action_reversal",
+    "funding_rate_oi",
 ]
 
 STRATEGY_DISPLAY: dict[str, str] = {
@@ -38,6 +41,9 @@ STRATEGY_DISPLAY: dict[str, str] = {
     "mfi": "Money Flow Index",
     "fvg": "Fair Value Gap",
     "candlestick": "Candlestick Patterns",
+    "liquidity_sweep": "Liquidity Sweep Detection",
+    "price_action_reversal": "Price Action Reversal",
+    "funding_rate_oi": "Funding Rate + OI",
 }