feat: establish project maintenance and trust foundation

[ericyangpan]

Summary

• restore CI, staging, scheduled URL validation, and GitHub Stars maintenance workflows
• fix search routing and coverage, model comparison localization/provider links/pricing, sitemap coverage, and current-year metadata
• add the model comparison selector and move pair pages from O(n²) static generation to on-demand ISR
• add structured provenance/freshness fields and public Verified badge semantics
• align contributor documentation, issue templates, script docs, and the project delivery tracker

Why

The project had accumulated workflow drift, stale contributor guidance, broken provider routes, expensive comparison generation, and no structured data provenance contract. This PR establishes a reliable baseline before the next data refresh and product iteration.

Impact

Users get correct search and comparison navigation, localized comparison labels, accurate pricing display, broader sitemap coverage, and no randomized fallback chart data. Maintainers get observable scheduled checks, deterministic generated-source enforcement, a weekly Stars refresh PR, and a tracked delivery plan.

Validation

• npm run biome:check
• npm run test:ci — 25 passed, 4 skipped
• npm run type-check
• npm run generate with no generated diff
• npm run build including Next.js and OpenNext Cloudflare bundle

[github-actions]

Preview deployment

Status	URL
Ready	https://pr-141-aicodingstack.pr-preview.workers.dev

Commit: ac1141f
Updated: 2026-07-17T23:11:31.917Z

[github-actions]

Preview deployment cleaned up

The preview deployment for PR #141 has been removed.