feat: Sprint 3-4 — Refacto API /v1/ (HRT-29)

- Blueprint Flask api_v1 avec prefix /api/v1/
- GET /api/v1/health — healthcheck public
- GET /api/v1/courses/today — courses du jour (paginé, filtré)
- GET /api/v1/courses/{id}/predictions — prédictions ML pour une course
- GET /api/v1/predictions/top3 — top 3 global (free tier)
- GET /api/v1/predictions/all — toutes prédictions (premium+)
- GET /api/v1/valuebets — value bets du jour (premium+)
- GET /api/v1/backtest — résultats backtest historiques (pro)
- GET /api/v1/export/csv — export CSV prédictions/paris (pro)
- GET /api/v1/metrics — métriques perf ML (premium+)
- Swagger/OpenAPI via flasgger à /api/v1/docs
- Erreurs uniformes {status, message, code}
- Pagination limit/offset sur toutes les listes
- 42 tests d'intégration passants

Co-Authored-By: Paperclip <noreply@paperclip.ing>

api_v1/routes/valuebets.py

@@ -0,0 +1,111 @@
+#!/usr/bin/env python3
+"""
+Value bets route for API v1.
+
+GET /api/v1/valuebets  — Value bets du jour (premium+)
+"""
+
+from datetime import datetime
+from flask import Blueprint, jsonify, request
+
+from api_v1.utils import (
+    get_db,
+    table_exists,
+    internal_error,
+    get_pagination_params,
+    paginate_query,
+)
+from auth import jwt_required_middleware, plan_required
+
+valuebets_bp = Blueprint("v1_valuebets", __name__, url_prefix="/api/v1")
+
+
+@valuebets_bp.route("/valuebets", methods=["GET"])
+@jwt_required_middleware
+@plan_required("premium", "pro")
+def valuebets():
+    """
+    Value bets du jour
+    ---
+    tags:
+      - Value Bets
+    summary: Value bets du jour — chevaux à cote surévaluée par le marché (premium+)
+    security:
+      - Bearer: []
+    parameters:
+      - name: date
+        in: query
+        type: string
+        format: date
+        description: Date YYYY-MM-DD (défaut aujourd'hui)
+      - name: min_odds
+        in: query
+        type: number
+        default: 2.0
+        description: Cote minimale pour filtrer les value bets
+      - name: limit
+        in: query
+        type: integer
+        default: 20
+      - name: offset
+        in: query
+        type: integer
+        default: 0
+    responses:
+      200:
+        description: Value bets du jour
+      401:
+        description: Token invalide
+      403:
+        description: Plan insuffisant (premium ou pro requis)
+    """
+    date_param = request.args.get("date", datetime.now().strftime("%Y-%m-%d"))
+    limit, offset = get_pagination_params(default_limit=20, max_limit=100)
+
+    try:
+        min_odds = float(request.args.get("min_odds", 2.0))
+    except (ValueError, TypeError):
+        min_odds = 2.0
+
+    conn = get_db()
+    try:
+        rows = []
+        total = 0
+
+        if table_exists(conn, "ml_predictions_cache"):
+            count_row = conn.execute(
+                """SELECT COUNT(*) as cnt
+                   FROM ml_predictions_cache
+                   WHERE date = ? AND is_value_bet = 1 AND odds >= ?""",
+                (date_param, min_odds),
+            ).fetchone()
+            total = count_row["cnt"] if count_row else 0
+
+            rows = conn.execute(
+                """SELECT race_label, hippodrome, discipline, distance, heure,
+                          horse_name, horse_number, odds, prob_top1, prob_top3,
+                          ml_score, recommendation, risque_label, risque_score
+                   FROM ml_predictions_cache
+                   WHERE date = ? AND is_value_bet = 1 AND odds >= ?
+                   ORDER BY ml_score DESC
+                   LIMIT ? OFFSET ?""",
+                (date_param, min_odds, limit, offset),
+            ).fetchall()
+
+        valuebets_list = [dict(r) for r in rows]
+        pagination = paginate_query(valuebets_list, total, limit, offset)
+
+        return jsonify(
+            {
+                "status": "ok",
+                "date": date_param,
+                "min_odds": min_odds,
+                "valuebets": valuebets_list,
+                **pagination,
+            }
+        ), 200
+
+    except Exception as e:
+        return internal_error(str(e))
+    finally:
+        conn.close()