Add client configuration validation on startup

[Just-Bamford]

Problem

Invalid client configs cause errors at runtime. No validation at creation time to catch issues early.

Solution

Implement comprehensive validation in \createSorokitClient(). Validates: network type, URLs, cache interface, logger interface. Returns detailed validation error if invalid.

Acceptance Criteria

• Validation added to \createSorokitClient()\
• Checks all required fields and types
• Validates URLs are well-formed
• Validates optional interfaces implement required methods
• Returns clear error message if invalid

Note for contributors

Reference \SorokitClientConfig\ interface. Add tests to \src/tests/client.test.ts.

[Glittersup]

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

Hi! I'd like to work on this issue.

The requirements are clear, and I'm comfortable working across different parts of the stack, including frontend, backend, smart contracts, and developer tooling. I'll follow the project's conventions, keep the implementation clean, and ensure it's properly tested before submitting.

Thanks!

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[Hollujay]

@Hollujay 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 because I will get it done.

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[sublime247]

@sublime247 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Please assign

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[drips-wave]

Congratulations, @sublime247! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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[drips-wave]

This issue has been completed by @sublime247 as part of the Stellar Wave Program's 7th Wave 🥳

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