fix(mcp): eager-auth flag so claude.ai's connector dialog detects OAuth, not "None" (#2159)

claude.ai's two-step "Add custom connector" dialog probes the server URL
without credentials and pre-fills the Authentication choice from the
answer. Our lazy-auth endpoint (issue #1814) answers 200 on an anonymous
initialize, which the dialog reads as an authless server: it suggests
"None", and a connector added with that default never opens the sign-in
when the challenge arrives later. Per Anthropic's connector docs a 401 is
the only answer it reads as OAuth ("Claude does not honor a
WWW-Authenticate header on a 200 response").

- `auth=required` on the endpoint URL (extensions/general/mcp-server/
  auth-mode.ts) turns lazy auth off for that URL: every tokenless
  request, initialize included, answers the 401 + WWW-Authenticate
  challenge. Callers with a token are unaffected; the bare URL keeps
  lazy auth for Claude Code, the plugin, Cursor and ChatGPT, and existing
  connector records are untouched.
- The links we control carry the flag: Settings -> API & MCP (install
  link and copy block), the onboarding checklist, both docs pages and
  claude-plugin/CONNECTORS.md (plugin 1.2.3). The docs' Path A now
  describes the eager flow (sign-in opens on Add) instead of telling
  users to override the dialog's "None".
- Tests: eager-auth.test.ts (401 on initialize/tools/list/public tools,
  namespaced metadata pointer, token no-op, exact-flag only); checklist
  link shape updated.

Companion: gnubok-website PR (Kom igång connector link + regenerated
connect-claude / anslut-claude pages).


Claude-Session: https://claude.ai/code/session_013yw62FMXGSzo6icFDiBwP3

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

claude-plugin/.claude-plugin/plugin.json

@@ -2,7 +2,7 @@
   "name": "accounted",
   "displayName": "Accounted",
   "description": "Official Accounted plugin: Swedish double-entry bookkeeping flows for Claude. Connects your ledger over MCP and ships short workflow skills (daily bookkeeping, health check, month close, VAT, payroll, year-end) that work from the company's live data and load Swedish accounting knowledge from the product when needed. Every write is staged for your approval; nothing is booked on its own.",
-  "version": "1.2.2",
+  "version": "1.2.3",
   "author": {
     "name": "Accounted (erp-mafia)"
   },