perf: optimize edge function latency with JWKS auth and lazy client creation (#13)

* perf: optimize edge function latency with JWKS auth and lazy client creation

- Replace eager Supabase client creation with lazy initialization
- Switch to JWKS-based JWT verification (production path)
- Add HS256 fallback for local development where JWKS is empty
- Expected improvement: /ping ~2000ms → ~50ms, DB routes ~2000ms → ~300ms

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* chore: regenerate deno.lock for esm.sh CDN changes

esm.sh CDN returned different content for webidl-conversions, causing
integrity check failures in CI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* chore: regenerate deno.lock for esm.sh CDN changes

esm.sh CDN returned different content for webidl-conversions, causing
integrity check failures in CI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix: update webidl-conversions hash for CI CDN edge

Different esm.sh CDN edge servers return different content.
Updated hash to match what GitHub Actions CI receives.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: justanotheratom