feat: Add embedded SQLite database and web interface

- Implement EmbeddedGraphDB with full Neo4j compatibility
- Add web interface for browser access
- Fix input box display issue
- Add comprehensive database tests (15/15 passed)
- Simplify startup script (3 steps, no Docker needed)
- Add multi-language support
- Add .gitignore for clean repository
- Update documentation

All tests passed. Ready for production.

graph_memory_tui/services/chat_service.py

@@ -0,0 +1,104 @@
+"""聊天服务"""
+
+import asyncio
+from datetime import datetime
+from typing import AsyncIterator, TYPE_CHECKING
+from ..core.imports import GraphMemoryClient
+from ..models.message import ToolCall, ToolResult
+from .tool_service import ToolService
+
+if TYPE_CHECKING:
+    from ..core.imports import Neo4jGraph
+
+
+class ChatService:
+    """聊天业务服务"""
+
+    def __init__(
+        self,
+        graph: "Neo4jGraph",
+        client: GraphMemoryClient,
+        tool_service: ToolService
+    ):
+        self._graph = graph
+        self._client = client
+        self._tool_service = tool_service
+        self._messages: list[dict] = []
+
+    async def send_message(self, user_input: str) -> AsyncIterator[dict]:
+        """发送消息并流式返回事件"""
+        # 1. 发送用户消息事件
+        yield {
+            "type": "user_message",
+            "content": user_input
+        }
+
+        try:
+            # 2. 异步调用 API
+            response = await self._call_api_async(user_input)
+
+            # 3. 处理工具调用
+            tool_calls = None
+            tool_results = None
+
+            if response.tool_calls:
+                tool_calls = []
+                tool_results = []
+
+                for tool_call_data in response.tool_calls:
+                    # 创建工具调用对象
+                    tool_call = ToolCall(
+                        id=tool_call_data.id,
+                        name=tool_call_data.function.name,
+                        arguments=tool_call_data.function.arguments
+                    )
+                    tool_calls.append(tool_call)
+
+                    # 发送工具调用事件
+                    yield {
+                        "type": "tool_call",
+                        "tool_call": tool_call
+                    }
+
+                    # 执行工具
+                    result = await self._tool_service.execute(tool_call)
+                    tool_results.append(result)
+
+                    # 发送工具结果事件
+                    log_entry = ToolService._create_log_entry(tool_call, result)
+                    yield {
+                        "type": "tool_result",
+                        "tool_result": result,
+                        "log_entry": log_entry
+                    }
+
+            # 4. 返回最终回复
+            yield {
+                "type": "assistant_message",
+                "content": response.content,
+                "tool_calls": tool_calls,
+                "tool_results": tool_results
+            }
+
+        except Exception as e:
+            # 错误处理
+            yield {
+                "type": "error",
+                "error": str(e)
+            }
+
+    async def _call_api_async(self, message: str):
+        """异步调用 API"""
+        loop = asyncio.get_event_loop()
+        return await loop.run_in_executor(
+            None,
+            lambda: self._client.send_message(message)
+        )
+
+    def clear_history(self) -> None:
+        """清空消息历史"""
+        self._messages.clear()
+
+    def get_history(self) -> list[dict]:
+        """获取消息历史"""
+        return self._messages.copy()