Gauge colors make them invisible in some cases

Hello,
With some of the Catppuccin themes, the gauges used in the copilot popup do not show up.

I believe it's because "gauge.background", "gauge.foreground" and their warning/error variants are way too transparent.

I worked around this by setting
```
"workbench.colorCustomizations": {
"[Catppuccin Macchiato]": {
"editorIndentGuide.background1": "#797a9c2e",
"gauge.background": "#9d9fc6ad",
"gauge.errorForeground": "#611905",
"gauge.errorBackground": "#b22d09",
}
},
```

Those colors do not fit catppuccin's palette but they fix my issue.

Note: I think there is an issue with VSCode's implementation as they inverted the gauge.foreground/gauge.background (and its error variant) in this popup: the filled part uses "background" and the ... background uses "foreground". I believe the official themes look great by accident.
I filed an issue there (https://github.com/microsoft/vscode/issues/256443), but even if VSCode fixes this issue, the theme will still show nothing

No file or test is named in the issue. Start by reproducing the copilot popup with the affected Catppuccin themes and inspect the theme color definitions for gauge.background, gauge.foreground, gauge.errorBackground, and gauge.errorForeground. Done means the gauges are visible while preserving the Catppuccin palette, including after the reported VSCode behavior is resolved.

Written by the indexing model from the issue text.