feat(server): add attachment schemas and GET /attachment/categories

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

tests/test_attachment_api.py

@@ -0,0 +1,30 @@
+from fastapi.testclient import TestClient
+from sqlalchemy.orm import Session
+
+from app.models.attachment import AttachmentCategory
+
+
+def _seed_categories(db: Session) -> list[int]:
+    cats = [
+        AttachmentCategory(name="TEST_CERT", sort_order=1, is_active=True),
+        AttachmentCategory(name="TEST_EXTRA", sort_order=2, is_active=True),
+        AttachmentCategory(name="TEST_OFF", sort_order=3, is_active=False),
+    ]
+    for c in cats:
+        db.add(c)
+    db.commit()
+    for c in cats:
+        db.refresh(c)
+    return [c.id for c in cats]
+
+
+def test_categories_lists_active_only(client: TestClient, db: Session):
+    _seed_categories(db)
+    resp = client.get("/CargoTrace/attachment/categories")
+    assert resp.status_code == 200
+    names = [c["name"] for c in resp.json()]
+    assert "TEST_CERT" in names
+    assert "TEST_EXTRA" in names
+    assert "TEST_OFF" not in names
+    # sorted by sort_order then name
+    assert names.index("TEST_CERT") < names.index("TEST_EXTRA")