Replace sandbox raw localStorage keys with storage-keys registry

[Abidoyesimze]

Summary

Sandbox persistence uses duplicated string literals instead of the shared key registry.

Affected files

• src/app/dashboard/sandbox/SandboxClientPage.tsx
• src/contexts/SandboxContext.tsx
• src/lib/storage-keys.ts

Tasks

• Replace inline localStorage key strings with constants from storage-keys.ts.
• Add missing keys to the registry if needed.
• Verify sandbox state still persists across reloads.

Acceptance criteria

• Scope is limited to the files listed (or agreed alternatives in the PR).
• Change is verifiable: tests, screenshots, or written QA steps in the PR.
• No behavior regressions in related user flows.
• No new duplicate abstractions without a one-line rationale in the PR.

Suggested labels

cleanup, refactor, good first issue

Notes

Standalone cleanup issue from CLEANUP_ISSUES_2026-05.md. Complements the audit queue and product backlog.

[aniokedianne]

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

I would like to work on this issue. I have experience with React, TypeScript, and frontend maintenance, and I'm confident I can audit the storage keys, make the necessary cleanup while avoiding regressions, verify the changes, and submit a clean PR.

Kindly assign this issue to me. Thank you!

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

[ola196]

@ola196 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Dear Maintainer please assign this issue to me I can resolve it

ℹ️ Repo Maintainers: To accept this application, review their application or assign @ola196 to this issue.

[kurehkim334-lang]

@kurehkim334-lang has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @kurehkim334-lang to this issue.

[Themancalledpg]

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

HI MAINTAINER
Please can I work on this issue? I'm a frontend developer and have full knowledge of resolving this issue

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

[drips-wave]

Congratulations, @kurehkim334-lang! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @kurehkim334-lang: 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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