Encode pagination cursors safely for Unicode ids

[greatest0fallt1me]

Summary

useCursorPagination.encodeCursor calls btoa(id) without try/catch; btoa throws InvalidCharacterError for characters outside Latin-1.

Why this matters

Once catalogue ids come from the backend, a single non-ASCII id crashes MarketplacePage's render.

Scope

Encode via TextEncoder + base64url (and decode symmetrically), keeping decodeCursor tolerant of invalid input.

Relevant code in CalloraOrg/Callora-Frontend:

• src/hooks/useCursorPagination.ts

Priority

Low

Acceptance criteria

• Ids with non-Latin-1 characters encode without throwing
• Round-trip decode returns the original id
• Cursors are URL-safe
• Invalid cursors still fall back to page one

Validation

npm test -- --run src/hooks/useCursorPagination.test.ts

Non-goals

• Typo-only, formatting-only, or cosmetic changes.
• Unrelated refactors, dependency upgrades, or broad rewrites.
• Removing safeguards or weakening validation to make tests pass.

Contributor application

Before coding, describe the affected modules, proposed state/invariant changes, test strategy, compatibility considerations, and an estimate. Wait for assignment before starting implementation.

PR requirements

Use a feature branch and include Closes #<issue-number>. Address every criterion, map criteria to code and tests, explain security and failure-mode handling, and ensure CI passes.

Quality review

A maintainer will assess correctness, completeness, test depth, compatibility, observability, and adverse-case handling. A substantive implementation is required; merge or CI status alone does not guarantee reward eligibility.

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Generated by Claude Code

[shobhamerabacha-star]

Hello @maintainers,

I would like to resolve this issue. Here is my proposed execution plan:

• Implementation: Deliver Keep leaderboard rank pages deterministic with proper loading/error states and clean component architecture.
• Testing: Verify UI performance and zero console errors.

Excited to work on this—please assign to me and I will submit a clean PR shortly!

[Killerjunior]

@Killerjunior has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer, I have read and understood the issue requirements and checked the necessary documentation. I’m confident I can work on this task effectively and deliver a proper solution.

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

[drips-wave]

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

🧑‍💻 @Killerjunior: 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.

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