refactor: remove mock trading functionality from backend and frontend

Removes all mock price simulation features:
- Delete MockPriceManager from backend/data/
- Remove mock_mode, enable_mock, is_mock_mode flags from services
- Remove mock CLI options and config
- Remove mock mode UI components and state from frontend
- Update tests to remove mock references

Now system supports only live and backtest modes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/api/runtime.py

@@ -181,7 +181,6 @@ class LaunchConfig(BaseModel):
     start_date: Optional[str] = Field(default=None, description="回测开始日期 YYYY-MM-DD")
     end_date: Optional[str] = Field(default=None, description="回测结束日期 YYYY-MM-DD")
     poll_interval: int = Field(default=10, ge=1, le=300, description="市场数据轮询间隔(秒)")
-    enable_mock: bool = Field(default=False, description="是否启用模拟模式(使用模拟价格数据)")
 
 
 class LaunchResponse(BaseModel):
@@ -756,7 +755,6 @@ async def start_runtime(
             "start_date": config.start_date,
             "end_date": config.end_date,
             "poll_interval": config.poll_interval,
-            "enable_mock": config.enable_mock,
         }
 
     retention_keep = max(1, int(os.getenv("RUNS_RETENTION_COUNT", "20") or "20"))