Add TypeScript strict mode and fix resulting type errors

[Akatenvictor]

What

Enable TypeScript strict mode in tsconfig.json and fix all resulting type errors to improve type safety across the codebase.

Why

Strict mode catches common type errors (null checks, implicit any, strict function types) that can cause runtime bugs. It's a best practice for production TypeScript.

Scope

In: Enable strict, strictNullChecks, noImplicitAny, fixAll resulting errors
Out: Strict property initialization, strict bind call apply

Acceptance Criteria

• "strict": true in tsconfig.json
• All type errors resolved
• No @ts-ignore or @ts-expect-error added as workarounds
• Proper null checks on all nullable values
• No implicit any in function parameters
• Build succeeds with strict mode

Technical Context

• Update tsconfig.json
• Fix errors incrementally (may be 50-100+ errors)
• Use strictNullChecks first as it catches the most bugs

[Teemi2106]

@Teemi2106 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would love to work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Teemi2106 to this issue.

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Congratulations, @balisdev! 🎉 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 @balisdev as part of the Stellar Wave Program's 7th Wave 🥳

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