Eliminate any type usage across the entire codebase

[nanaf6203-bit]

Problem

Hundreds of any type annotations across the codebase in services, controllers, guards, and tests. While some uses are unavoidable, the vast majority represent missed typing opportunities.

Why It Matters

The ESLint config already warns on @typescript-eslint/no-explicit-any (set to warn), but the codebase doesn't respect this rule. any disables TypeScript's type checker entirely.

Technical Context

Found in critical paths: src/auth/auth.service.ts (DTOs, API responses, token payloads), src/transactions/transactions.service.ts (Prisma queries, DTO mappings), src/admin/admin.service.ts (query builders), src/dashboard/dashboard.service.ts (data transformations).

Expected Outcome

Zero any usages in production code (except unavoidable third-party interop).

Acceptance Criteria

• All production source files have zero any annotations
• Generic types () used where appropriate
• Proper interfaces created for complex data structures
• @typescript-eslint/no-explicit-any rule set to error
• Build passes with the stricter rule

Files Affected

src/**/*.ts (widespread)

Difficulty

Hard

Estimated Effort

Extra Large (project-wide)

Labels

type-safe, refactoring, tech-debt

[abdoolyaro]

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

Hi, I’d like to take this issue. I can systematically eliminate any usages across the production codebase by introducing proper interfaces, generics, and inferred types where appropriate, update the ESLint rule to treat no-explicit-any as an error, and ensure the project builds and tests successfully under the stricter type-safety requirements.

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

[drips-wave]

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

🧑‍💻 @abdoolyaro: 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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