fix: prevent flickering by removing auto color scheme and default background color

[Meierschlumpf]

Homarr

Thank you for your contribution. Please ensure that your pull request meets the following pull request:

• Builds without warnings or errors (pnpm buid, autofix with pnpm format:fix)
• Pull request targets dev branch
• Commits follow the conventional commits guideline
• No shorthand variable names are used (eg. x, y, i or any abbrevation)

Closes https://discord.com/channels/972958686051962910/1295792744601616414

[deepsource-io]

Here's the code health analysis summary for commits bb0026a..ef2a964. View details on DeepSource ↗.

Analysis Summary

Analyzer	Status	Summary	Link
JavaScript	✅ Success		View Check ↗

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[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	38.96%	14521 / 37267
🔵	Statements	38.96%	14521 / 37267
🔵	Functions	35.94%	376 / 1046
🔵	Branches	70.79%	1287 / 1818

File Coverage

File	Stmts	% Branch	% Funcs	% Lines	Uncovered Lines
Changed Files
apps/nextjs/src/app/[locale]/layout.tsx	0%	0%	0%	0%	1-2, 4-7, 9, 11-15, 17-24, 26-29, 31-48, 50-55, 57-61, 63-72, 74, 76-83, 85-95, 97
apps/nextjs/src/app/[locale]/_client-providers/mantine.tsx	0%	0%	0%	0%	1, 4, 6-7, 9-11, 13-14, 16-24, 26-28, 30, 32-42, 44, 46-50, 52-54, 56-62, 64-75, 77-83, 85-86, 88-90, 92-96
packages/auth/callbacks.ts	75.47%	100%	66.66%	75.47%	30-42
packages/db/schema/mysql.ts	100%	100%	100%	100%
packages/db/schema/sqlite.ts	100%	100%	100%	100%
packages/definitions/src/user.ts	100%	100%	100%	100%

Generated in workflow #3266 for commit ef2a964 by the Vitest Coverage Report Action