[Saifjafri212213]

Summary

A dedicated Next.js App Router adapter (chatcopsNext()) that serves both the chat and session endpoints from a single catch-all route (app/api/chat/[[...path]]/route.ts), replacing the previous two-file requirement (route.ts and session/route.ts).

Closes #574

Why

Today, Next.js setups need two route files: app/api/chat/route.ts and app/api/chat/session/route.ts (which re-exports POST and OPTIONS). Forgetting the second one quietly breaks session tokens with 404s when the chat tries to initialize.

Next.js optional catch-all routes ([[...path]]) let a single route file handle every subpath under /api/chat. fetchChatResponse() in packages/server/src/http.ts already routes paths ending in /session to the session endpoint via isSessionPath(), so the catch-all works without needing internal routing of its own.

What changed

• @chatcops/server:
  • packages/server/src/adapters/next.ts (new): chatcopsNext(config). It creates createChatHandler and originPolicy at module scope and returns { POST, OPTIONS }, both (request: Request) => Promise<Response>. Client IP resolution and rate limits work across calls as in chatcopsVercelHandler.
  • Added "./next" to exports in packages/server/package.json alongside "./vercel", and re-exported chatcopsNext from packages/server/src/index.ts.
• Docs:
  • Updated the Next.js App Router section in website/src/content/docs/server/fetch-runtimes.mdx to the single catch-all route, with a short note explaining the older two-file setup.
  • Added chatcopsNext to scripts/check-doc-samples.mjs so pnpm docs:check validates that Next doc samples configure session secrets or allow anonymous access.
• Changeset & API: Minor changeset for @chatcops/server, and committed the updated API snapshot in api/server.api.md.

Notes for review

• chatcopsNext returns { POST, OPTIONS }. A GET handler is left for later with visitor handoff (F-10), as noted in the issue.
• Both POST and OPTIONS point to the single handler, so CORS preflight and chat/session POSTs are handled by fetchChatResponse().

How I Tested This

• packages/server/tests/adapters/next.test.ts (4 new tests with real Request objects):
  • OPTIONS preflight returning 204 with CORS headers.
  • Session POST to /api/chat/session minting a session token (200).
  • Chat POST to /api/chat without a token returning 401 (session_required).
  • Chat POST with the session Bearer token streaming the SSE reply (200).
• Coverage: 100% statement, branch, function, and line coverage on src/adapters/next.ts.
• Verified in a fresh Next.js app (npx create-next-app@latest) with app/api/chat/[[...path]]/route.ts using chatcopsNext().
• Local checks: pnpm docs:check passes (204 blocks checked, 3 skipped), pnpm api:check is up to date, pnpm publint reports all good, pnpm lint has 0 errors (38 warnings, same as dev), and pnpm -r typecheck passes cleanly.