Dark mode polish + system-preference sync

[truthixify]

Extra labels: ux
Tier: S (1-2 days) | Type: ux

Context. Dark mode exists but isn't polished (contrast issues on activity table, missing color for warning states) and doesn't sync with OS preference.

Scope.

• Audit contrast on every Stellar page in dark mode.
• Bind theme to prefers-color-scheme by default, override via toggle.
• Persist explicit override.
• Add a "system default" tri-state.

Acceptance.

• Contrast passes WCAG 2.1 AA everywhere
• OS theme change reflects live (no reload)
• Explicit override survives reload

Files. src/context/ThemeContext.tsx, src/pages/Settings.tsx, Tailwind config.

[amosleoamadi]

@amosleoamadi has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Can I work on this please

ℹ️ Repo Maintainers: To accept this application, review their application or assign @amosleoamadi to this issue.

[shaarknado]

@shaarknado has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

i would love to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @shaarknado to this issue.

[drips-wave]

Congratulations, @amosleoamadi! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @amosleoamadi: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊

[drips-wave]

This issue has been completed by @amosleoamadi as part of the Stellar Wave Program's 7th Wave 🥳

😎 @amosleoamadi: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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