Add SDK browser bundle build

[Haroldwonder]

Overview\nThe SDK currently outputs CJS and ESM for Node.js. Add a browser-optimized UMD/ESM bundle that can be loaded from a CDN.\n\n## Tasks\n- [ ] Add browser entry to tsup.config.ts\n- [ ] Ensure no Node.js built-ins leak into the browser bundle\n- [ ] Add bundle size check in CI (warn if > 100 KB gzipped)\n- [ ] Test in a plain <script type="module"> environment\n\n## Acceptance Criteria\n- @swiftremit/sdk is usable in a browser without a bundler

[Waffiyyi]

@Waffiyyi has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I would love to work on this issue. Please assign this to me.

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[Isle-of-Bonita]

@Darkvader-ship-it has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

can i work on this

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[midexol]

@midexol has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

hi maintainer, I'd love to resolve this issue, please assign. Thank you

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[Diyaq]

@Diyaq has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I would like to work on this issue

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[Eyanus]

@Eyanus has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello Maintainers,

I’d like to work on this issue. I understand the requirements and I’m confident I can implement a clean and reliable solution following the project’s standards, including proper testing.

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[nikkybel]

@nikkybel has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Please can I be assign this issue to tackle?

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[drips-wave]

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

🧑‍💻 @Diyaq: 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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