[Backend] Admin and indexer mutation routes use ad-hoc inline validation instead of zod middleware

[grantfox-oss]

Telegram (ask questions / claim the issue here first): https://t.me/+DOylgFv1jyJlNzM0

Why this matters

Several mutating endpoints (webhook creation in src/controllers/indexerController.ts lines 494-520, reindex and quarantine-reprocess in adminRoutes) validate input with hand-written checks rather than the project's validate() + zod pattern used elsewhere, leading to inconsistent error shapes and gaps.

Acceptance criteria

• Define zod schemas for webhook creation, reindex query params and quarantine reprocess bodies
• Apply the existing validation middleware and remove the inline checks
• Ensure error responses match the standardized zod error format from errorHandler
• Add tests for invalid inputs on these routes

Files to touch

• src/controllers/indexerController.ts
• src/routes/adminRoutes.ts
• src/routes/indexerRoutes.ts
• src/middleware/validation.ts

Out of scope

• Reworking the auth model on these routes
• Adding new endpoints

[anonfedora]

I'd like to work on this issue because it aligns with my experience building TypeScript backends with Zod-based validation patterns.

I have experience replacing ad hoc input checks with centralized schema validation, implementing reusable middleware, and ensuring consistent API error responses. I'm confident in defining the required schemas, integrating them with the existing validation flow, and adding comprehensive tests for invalid input scenarios.

[grantfox-oss]

🦊 GrantFox — @anonfedora has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #17)
2. Your PR will be reviewed by the LabsCrypt maintainers

Good luck! Track your progress on GrantFox.