Social links: rate limiting on create/update

[iGEORGE17]

feat: add rate limiting to social links create and update endpoints

Summary

Adds rate limiting to the POST /social-links and PATCH /social-links/:id endpoints to prevent abuse. Excess requests return 429 Too Many Requests. Uses the existing @nestjs/throttler package already present in the project — no new dependencies added.

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Changes

• Added @UseGuards(ThrottlerGuard) and @Throttle({ default: { limit: 5, ttl: 60 } }) to create and update methods in SocialLinkController
• Registered ThrottlerModule.forRoot([{ ttl: 60, limit: 10 }]) in AppModule
• Throttling is scoped to social links only — APP_GUARD is not used globally
• Added integration test that hits POST /social-links 5 times then expects 429 on the 6th request

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How to Test

npm test -- social-links

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Acceptance Criteria

Criteria	Status
Excess requests get 429	✅
Limit is per user or IP	✅ ThrottlerGuard tracks by IP by default
Tests pass	✅

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Notes

• Uses @nestjs/throttler v6.5.0 already in the project — no new packages added
• Limit of 5 requests per 60 seconds per IP — can be adjusted in the @Throttle decorator
• @Throttle uses v6 object syntax: { default: { limit, ttl } }

Closes #210

[aji70]

LFG