fix: use BigInteger for size_bytes to support files >2 GB

Fixes psycopg2 NumericValueOutOfRange when mock provider returns
size_bytes=4_000_000_000. Adds regression test for >2.15 GB payload.

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

backend/src/models.py

@@ -1,6 +1,6 @@
 import enum
 from datetime import datetime
-from sqlalchemy import String, Integer, Float, DateTime, Enum as SAEnum, func
+from sqlalchemy import String, Integer, BigInteger, Float, DateTime, Enum as SAEnum, func
 from sqlalchemy.orm import Mapped, mapped_column
 from .database import Base
 
@@ -23,7 +23,7 @@ class Download(Base):
     provider: Mapped[str] = mapped_column(String(100))
     quality: Mapped[str | None] = mapped_column(String(50), nullable=True)
     language: Mapped[str | None] = mapped_column(String(50), nullable=True)
-    size_bytes: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    size_bytes: Mapped[int | None] = mapped_column(BigInteger, nullable=True)
     status: Mapped[DownloadStatus] = mapped_column(
         SAEnum(DownloadStatus), default=DownloadStatus.pending
     )

backend/tests/test_downloads.py

@@ -0,0 +1,45 @@
+from fastapi.testclient import TestClient
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+from sqlalchemy.pool import StaticPool
+
+from src.database import Base
+from src.main import app, get_db
+
+
+engine = create_engine(
+    "sqlite://",
+    connect_args={"check_same_thread": False},
+    poolclass=StaticPool,
+)
+TestingSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+Base.metadata.create_all(bind=engine)
+
+
+def override_get_db():
+    db = TestingSessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
+
+
+app.dependency_overrides[get_db] = override_get_db
+client = TestClient(app)
+
+
+def test_create_download_accepts_mock_provider_size_bytes():
+    response = client.post(
+        "/api/downloads",
+        json={
+            "title": "inception (Mock Result 1)",
+            "url": "mock://inception/1",
+            "provider": "mock",
+            "quality": "1080p",
+            "language": "en",
+            "size_bytes": 4_000_000_000,
+        },
+    )
+
+    assert response.status_code == 201
+    assert response.json()["size_bytes"] == 4_000_000_000

worker/src/worker.py

@@ -7,7 +7,7 @@ import time
 import logging
 from sqlalchemy import create_engine, select
 from sqlalchemy.orm import Session, DeclarativeBase, Mapped, mapped_column
-from sqlalchemy import String, Integer, Float, DateTime, Enum as SAEnum, func
+from sqlalchemy import String, Integer, BigInteger, Float, DateTime, Enum as SAEnum, func
 import enum
 from pydantic_settings import BaseSettings
 
@@ -50,7 +50,7 @@ class Download(Base):
     provider: Mapped[str] = mapped_column(String(100))
     quality: Mapped[str | None] = mapped_column(String(50), nullable=True)
     language: Mapped[str | None] = mapped_column(String(50), nullable=True)
-    size_bytes: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    size_bytes: Mapped[int | None] = mapped_column(BigInteger, nullable=True)
     status: Mapped[DownloadStatus] = mapped_column(
         SAEnum(DownloadStatus), default=DownloadStatus.pending
     )