Honor YOLO preflight environment config

backend/tests/test_sprint13_yolo_preflight.py

@@ -197,6 +197,36 @@ def test_yolo_preflight_script_outputs_json(tmp_path: Path) -> None:
     assert payload["tile_manifest_path"] == str(manifest_path)
 
 
+def test_yolo_preflight_script_uses_environment_configuration(tmp_path: Path, monkeypatch) -> None:
+    model_path = tmp_path / "model.pt"
+    model_path.write_bytes(b"weights")
+    manifest_path = _manifest(tmp_path)
+    monkeypatch.setenv("YOLO_ENABLED", "true")
+    monkeypatch.setenv("YOLO_MODEL_PATH", str(model_path))
+    monkeypatch.setenv("YOLO_MAX_TILES", "4")
+
+    result = subprocess.run(
+        [
+            sys.executable,
+            str(ROOT / "scripts" / "yolo_preflight.py"),
+            "--tile-manifest-path",
+            str(manifest_path),
+            "--assume-dependencies",
+            "--json",
+        ],
+        cwd=ROOT,
+        check=True,
+        capture_output=True,
+        text=True,
+    )
+    payload = json.loads(result.stdout)
+
+    assert payload["status"] == "ready"
+    assert payload["checks"]["enabled"] is True
+    assert payload["model_path"] == str(model_path)
+    assert payload["max_tiles"] == 4
+
+
 def test_yolo_preflight_script_rejects_assumed_dependencies_for_model_load(tmp_path: Path) -> None:
     result = subprocess.run(
         [