fix: OPTIC-2120: LSO: All Projects navigation bar is transparent

[yyassi-heartex]

This pull request updates the styling of the Projects page in the web/apps/labelstudio application to enhance visual consistency and improve the user interface.

Styling updates:

• web/apps/labelstudio/src/pages/Projects/Projects.scss: Changed the background-color of the __pages class from transparent to a variable --color-neutral-background for better theme consistency. Added a top border with --color-neutral-border to visually separate sections.

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[yyassi-heartex]

/git merge

Workflow run
Successfully merged: create mode 100644 web/libs/core/src/lib/utils/query-client.ts