Chart showing negative response-time

**Describe the bug**
Response-time ms chart is showing negative number.

**Database**
- sqlite

**To Reproduce**
1. Run with `docker run -d --restart=always -p 8383:8383 -e DB_NAME=/app/data/peekaping.db -v ${PWD}/.data/sqlite:/app/data 0xfurai/peekaping-bundle-sqlite:latest`
2. Create a new monitor and leave everything as is (on `https://example.com`)

**Expected behavior**
The chart should show positive numbers, not negative numbers.

**Screenshots**

**Desktop (please complete the following information):**
- Windows 11
- Chrome Browser
- Docker Desktop v4.47
- Image: [docker hub](https://hub.docker.com/layers/0xfurai/peekaping-bundle-sqlite/latest/images/sha256-695264a720b243c1fb56ebfc30fdc7a6169a62c49fe9b637745bc4a495fb80c2)

The issue is about a chart displaying negative response times. Start by examining the code that calculates and renders response-time metrics, likely in a frontend chart component or the backend API that serves the data. Check the data transformation logic for any sign miscalculations. Look at the monitor creation and data aggregation flow to see where the negative values originate. Verify by running the provided Docker command and inspecting the stored response time values in the SQLite database.

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