Rename "Stop" to "Close Window" button within the log viewer

**Describe the problem you have/What new integration you would like**
The existing "Stop" button name may trick a user to think that it will stop the actual ESP device, while it's only closing the Log Viewer window

**Please describe your use case for this integration and alternatives you've tried:**
It's fine to keep using "Stop" button as is, after the initial learning curve. However new "Close Windows" button name may slightly improve ESPHome newcomer experience.

**Additional context**

The issue concerns the Log Viewer’s “Stop” button, but it does not name a source file, entry point, or test. Start by locating the Log Viewer UI and its button label; done means the control is renamed to “Close Window” without implying that the ESP device itself will stop.

Written by the indexing model from the issue text.