feat: add LoraDemoNode and LoraRandomizerNode with documentation

- Import and register two new nodes: LoraDemoNode and LoraRandomizerNode
- Update import exception handling for better readability with multi-line formatting
- Add comprehensive documentation file `docs/custom-node-ui-output.md` for UI output usage in custom nodes
- Ensure proper node registration in NODE_CLASS_MAPPINGS for ComfyUI integration
- Maintain backward compatibility with existing node structure and import fallbacks

tests/routes/test_randomizer_endpoints.py

@@ -0,0 +1,191 @@
+import json
+from unittest.mock import MagicMock
+
+import pytest
+
+from py.routes.lora_routes import LoraRoutes
+
+
+class DummyRequest:
+    def __init__(self, *, query=None, match_info=None, json_data=None):
+        self.query = query or {}
+        self.match_info = match_info or {}
+        self._json_data = json_data or {}
+
+    async def json(self):
+        return self._json_data
+
+
+class StubLoraService:
+    """Stub service for testing randomizer endpoints"""
+
+    def __init__(self):
+        self.random_loras = []
+
+    async def get_random_loras(self, **kwargs):
+        return self.random_loras
+
+
+@pytest.fixture
+def routes():
+    handler = LoraRoutes()
+    handler.service = StubLoraService()
+    return handler
+
+
+async def test_get_random_loras_success(routes):
+    """Test successful random LoRA generation"""
+    routes.service.random_loras = [
+        {
+            'name': 'test_lora_1',
+            'strength': 0.8,
+            'clipStrength': 0.8,
+            'active': True,
+            'expanded': False,
+            'locked': False
+        },
+        {
+            'name': 'test_lora_2',
+            'strength': 0.6,
+            'clipStrength': 0.6,
+            'active': True,
+            'expanded': False,
+            'locked': False
+        }
+    ]
+
+    request = DummyRequest(json_data={
+        'count': 5,
+        'model_strength_min': 0.5,
+        'model_strength_max': 1.0,
+        'use_same_clip_strength': True,
+        'locked_loras': []
+    })
+
+    response = await routes.get_random_loras(request)
+    payload = json.loads(response.text)
+
+    assert response.status == 200
+    assert payload['success'] is True
+    assert 'loras' in payload
+    assert payload['count'] == 2
+
+
+async def test_get_random_loras_with_range(routes):
+    """Test random LoRAs with count range"""
+    routes.service.random_loras = [
+        {
+            'name': 'test_lora_1',
+            'strength': 0.8,
+            'clipStrength': 0.8,
+            'active': True,
+            'expanded': False,
+            'locked': False
+        }
+    ]
+
+    request = DummyRequest(json_data={
+        'count_min': 3,
+        'count_max': 7,
+        'model_strength_min': 0.0,
+        'model_strength_max': 1.0,
+        'use_same_clip_strength': True
+    })
+
+    response = await routes.get_random_loras(request)
+    payload = json.loads(response.text)
+
+    assert response.status == 200
+    assert payload['success'] is True
+
+
+async def test_get_random_loras_invalid_count(routes):
+    """Test invalid count parameter"""
+    request = DummyRequest(json_data={
+        'count': 150,  # Over limit
+        'model_strength_min': 0.0,
+        'model_strength_max': 1.0
+    })
+
+    response = await routes.get_random_loras(request)
+    payload = json.loads(response.text)
+
+    assert response.status == 400
+    assert payload['success'] is False
+    assert 'Count must be between 1 and 100' in payload['error']
+
+
+async def test_get_random_loras_invalid_strength(routes):
+    """Test invalid strength range"""
+    request = DummyRequest(json_data={
+        'count': 5,
+        'model_strength_min': -0.5,  # Invalid
+        'model_strength_max': 1.0
+    })
+
+    response = await routes.get_random_loras(request)
+    payload = json.loads(response.text)
+
+    assert response.status == 400
+    assert payload['success'] is False
+
+
+async def test_get_random_loras_with_locked(routes):
+    """Test random LoRAs with locked items"""
+    routes.service.random_loras = [
+        {
+            'name': 'new_lora',
+            'strength': 0.7,
+            'clipStrength': 0.7,
+            'active': True,
+            'expanded': False,
+            'locked': False
+        },
+        {
+            'name': 'locked_lora',
+            'strength': 0.9,
+            'clipStrength': 0.9,
+            'active': True,
+            'expanded': False,
+            'locked': True
+        }
+    ]
+
+    request = DummyRequest(json_data={
+        'count': 5,
+        'model_strength_min': 0.5,
+        'model_strength_max': 1.0,
+        'use_same_clip_strength': True,
+        'locked_loras': [
+            {
+                'name': 'locked_lora',
+                'strength': 0.9,
+                'clipStrength': 0.9,
+                'active': True,
+                'expanded': False,
+                'locked': True
+            }
+        ]
+    })
+
+    response = await routes.get_random_loras(request)
+    payload = json.loads(response.text)
+
+    assert response.status == 200
+    assert payload['success'] is True
+
+
+async def test_get_random_loras_error(routes, monkeypatch):
+    """Test error handling"""
+    async def failing(*_args, **_kwargs):
+        raise RuntimeError("Service error")
+
+    routes.service.get_random_loras = failing
+    request = DummyRequest(json_data={'count': 5})
+
+    response = await routes.get_random_loras(request)
+    payload = json.loads(response.text)
+
+    assert response.status == 500
+    assert payload['success'] is False
+    assert 'error' in payload