fix(cli): point logicsrc login at the real app + add device-code login

`logicsrc login` defaulted to http://localhost:4010 — a dev origin that
doesn't exist on an installed machine, so the printed authorize URL went
nowhere. It now defaults to the hosted credentials app (apps/pwa), reads
the documented $LOGICSRC_API, and only reuses a stored apiUrl once that
identity has actually completed a login (which is how machines got stuck
pointing at localhost). Note logicsrc.com is the marketing site and has
no /cli routes.

The loopback flow is also unusable over SSH: redirect_uri is
http://127.0.0.1:<port>/callback, which resolves to the *browser's*
machine, not the CLI's. Added a device-authorization flow — the CLI
prints a short user_code, the human approves it from any browser:

  POST /cli/device/code   mint device_code + user_code (10 min TTL)
  GET  /cli/device        approve page (login required; typo-tolerant)
  POST /cli/device        approve/deny (CSRF-guarded browser form)
  POST /cli/device/token  CLI polls -> lsk_ API key

device_code is stored sha256-hashed, single-use, with authorization_pending
/ slow_down / access_denied / expired_token poll semantics. The CLI picks
the flow automatically (SSH/CI/no-DISPLAY -> device), with --device/--web
to force it and a fallback to loopback against servers without /cli/device.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

plugins/credential-sharing/src/index.ts

@@ -89,6 +89,9 @@ export {
   identityPath,
   logicsrcHome,
   defaultApiUrl,
+  envApiUrl,
+  resolveApiUrl,
+  DEFAULT_API_URL,
   type LocalIdentity
 } from "./identity.js";
 export {