feat: merge cartsnitch/api into api/ subdirectory

Consolidate API gateway service into monorepo.
Squashed from https://github.com/cartsnitch/api main (89bacb1).

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

tests/test_routes/test_stores.py

@@ -0,0 +1,77 @@
+"""Integration tests for store endpoints."""
+
+import pytest
+
+from cartsnitch_api.models import Store
+
+
+@pytest.fixture
+async def seeded_store(db_engine):
+    """Insert a test store directly into the DB."""
+    from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker
+
+    factory = async_sessionmaker(db_engine, class_=AsyncSession, expire_on_commit=False)
+    async with factory() as session:
+        store = Store(name="Meijer", slug="meijer", logo_url=None, website_url=None)
+        session.add(store)
+        await session.commit()
+        await session.refresh(store)
+        return store
+
+
+@pytest.mark.asyncio
+async def test_list_stores(client, seeded_store):
+    resp = await client.get("/stores")
+    assert resp.status_code == 200
+    data = resp.json()
+    assert len(data) >= 1
+    assert data[0]["slug"] == "meijer"
+
+
+@pytest.mark.asyncio
+async def test_list_user_stores_empty(client, auth_headers):
+    resp = await client.get("/me/stores", headers=auth_headers)
+    assert resp.status_code == 200
+    assert resp.json() == []
+
+
+@pytest.mark.asyncio
+async def test_connect_and_disconnect_store(client, auth_headers, seeded_store):
+    # Connect
+    resp = await client.post(
+        "/me/stores/meijer/connect",
+        headers=auth_headers,
+        json={"credentials": None},
+    )
+    assert resp.status_code == 201
+    assert resp.json()["connected"] is True
+
+    # List should show connected
+    resp = await client.get("/me/stores", headers=auth_headers)
+    assert resp.status_code == 200
+    assert len(resp.json()) == 1
+
+    # Disconnect
+    resp = await client.delete("/me/stores/meijer", headers=auth_headers)
+    assert resp.status_code == 204
+
+    # List should be empty again
+    resp = await client.get("/me/stores", headers=auth_headers)
+    assert resp.json() == []
+
+
+@pytest.mark.asyncio
+async def test_connect_nonexistent_store(client, auth_headers):
+    resp = await client.post(
+        "/me/stores/nonexistent/connect",
+        headers=auth_headers,
+        json={},
+    )
+    assert resp.status_code == 404
+
+
+@pytest.mark.asyncio
+async def test_connect_duplicate_store(client, auth_headers, seeded_store):
+    await client.post("/me/stores/meijer/connect", headers=auth_headers, json={})
+    resp = await client.post("/me/stores/meijer/connect", headers=auth_headers, json={})
+    assert resp.status_code == 409