feat(performance): persist and aggregate Web Vitals metrics

[MerlinTheWhiz]

Description

Persists incoming Web Vitals metrics to a new web_vitals database table, exposes aggregated data via a GET endpoint, and adds poor-rate alerting when a metric exceeds the 5% threshold.

Changes:

• Created src/lib/db/migrations/001_create_web_vitals.sql (table DDL with indexes on name, page_url, created_at, rating)
• Created src/lib/db/migrate.ts — migration runner that tracks applied migrations in a _migrations table
• Modified src/app/api/performance/vitals/route.ts:
  • Changed runtime from edge → nodejs (required for pg access)
  • POST: validates incoming metrics, inserts a row into web_vitals, keeps existing console alerts, and fires an additional alert if poor-rate exceeds 5% over the last 500 sessions
  • GET: new handler returning aggregated metrics (avg_value, poor_rate_pct) grouped by name and page_url, with a configurable ?range=7d|30d|90d|all query parameter
• Added migrate script to package.json

Related Issue

Closes #764

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Checklist

• Code follows project style guidelines
• Self-review completed
• No console errors
• Uses Lucide icons consistently
• Responsive design implemented
• Starknet best practices followed

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[RUKAYAT-CODER]

Great job so far

There’s just one blocker — the workflow is failing. Could you take a look and fix it so all checks pass?

Happy to review again once that’s done.
You can pull from the main first before pushing. The workflow should pass

[MerlinTheWhiz]

@RUKAYAT-CODER It was from my edits. I've resolved the issues now, you can merge now. All green.

[MerlinTheWhiz]

@RUKAYAT-CODER Please hold, don't merge yet.

[MerlinTheWhiz]

@RUKAYAT-CODER You can merge now. Thanks

[RUKAYAT-CODER]

Kindly resolve conflict