End 2 end tests (#2266)

* All endpoints covered

test_integration.py kept for backwards compatability.
tests/integration/run_all.py proposed as alternative to cover all endpoints.

* Linter fixes

tests/integration/__init__.py

@@ -0,0 +1,64 @@
+"""
+DocsGPT Integration Tests Package
+
+This package contains modular integration tests for all DocsGPT API endpoints.
+Tests are organized by domain:
+
+- test_chat.py: Chat/streaming endpoints (/stream, /api/answer, /api/feedback, /api/tts)
+- test_sources.py: Source management (upload, remote, chunks, etc.)
+- test_agents.py: Agent CRUD and sharing
+- test_conversations.py: Conversation management
+- test_prompts.py: Prompt CRUD
+- test_tools.py: Tools CRUD
+- test_analytics.py: Analytics endpoints
+- test_connectors.py: External connectors
+- test_mcp.py: MCP server endpoints
+- test_misc.py: Models, images, attachments
+
+Usage:
+    # Run all integration tests
+    python tests/integration/run_all.py
+
+    # Run specific module
+    python tests/integration/test_chat.py
+
+    # Run multiple modules
+    python tests/integration/run_all.py --module chat,agents
+
+    # Run with custom server
+    python tests/integration/run_all.py --base-url http://localhost:7091
+
+    # List available modules
+    python tests/integration/run_all.py --list
+"""
+
+from .base import Colors, DocsGPTTestBase, create_client_from_args, generate_jwt_token
+from .test_chat import ChatTests
+from .test_sources import SourceTests
+from .test_agents import AgentTests
+from .test_conversations import ConversationTests
+from .test_prompts import PromptTests
+from .test_tools import ToolsTests
+from .test_analytics import AnalyticsTests
+from .test_connectors import ConnectorTests
+from .test_mcp import MCPTests
+from .test_misc import MiscTests
+
+__all__ = [
+    # Base utilities
+    "Colors",
+    "DocsGPTTestBase",
+    "create_client_from_args",
+    "generate_jwt_token",
+    # Test classes
+    "ChatTests",
+    "SourceTests",
+    "AgentTests",
+    "ConversationTests",
+    "PromptTests",
+    "ToolsTests",
+    "AnalyticsTests",
+    "ConnectorTests",
+    "MCPTests",
+    "MiscTests",
+]