ci: setup jsr publishing

[mandarini]

Summary

Adds JSR (jsr.io) publishing so @supabase/server can be consumed natively by Deno users via jsr:@supabase/server.

What changed

• jsr.json -- new package config with all three export entry points (., ./core, ./adapters/hono) pointing to TypeScript source files
• release-please-config.json -- added jsr.json to extra-files so release-please bumps the version in both package.json and jsr.json atomically
• release.yml -- added a "Publish to JSR" step after npm publish, using OIDC auth (id-token: write was already configured). Runs with continue-on-error: true so JSR failures never block the npm release
• ci.yml -- added a jsr publish --dry-run step to catch packaging errors (slow types, bad exports) on every push/PR
• src/errors.ts -- added explicit return type annotations to all arrow functions in EnvErrorMap and AuthErrorMap (required by JSR's "no slow types" rule since the Errors object is publicly exported)
• src/adapters/hono/middleware.ts -- added explicit MiddlewareHandler return type to the exported withSupabase function (same reason)

Design decisions

• Version managed by release-please, not a CI-stamped placeholder. The extra-files config uses release-please's built-in GenericJson updater for .json files.
• No separate publish script -- the workflow step is a single npx jsr publish --allow-dirty since all version management is handled by release-please.
• JSR publishes from source (.ts files), not from dist/. The publish.include field scopes what gets uploaded.
• Non-blocking -- mirrors the pattern used in supabase-js where JSR is secondary to npm.

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@supabase/server@37

commit: 0d3a96e