Add OIDC login and per-domain authorization

Authentication previously implied full authorization: any valid token
could manage every host, DNS provider, domain, and user. This adds SSO
login and a per-domain rights model.

OIDC login (authorization_code + PKCE):
- conf.oidc + conf.auth blocks; clientSecret in (gitignored) secrets.js.
- utils/oidc.js (state/PKCE, code exchange, userinfo) using global fetch.
- models/oidc_state.js: short-lived state store, auto-expiring via
  model-redis 1.5 per-key TTL.
- routes/auth.js: GET /auth/oidc/start + /auth/oidc/callback; JIT-provisions
  a local user, mints an AuthToken carrying the SSO groups, hands the token to
  the browser via a URL fragment. "Log in with SSO" button on the login page.

Authorization (groups + app overrides, per-domain, with ownership):
- models/grant.js + utils/roles.js (pure, unit-tested): effective rights from
  conf.auth (admin users/groups, group->role map), Grant records
  (user|group -> global|domain -> viewer|manager|admin), and ownership
  (created_by). Roles rank admin > manager(owner) > viewer.
- AuthToken stores session groups; middleware/auth.js exposes req.groups.
- middleware/authz.js: requireAdmin, requireDomainRole(minRole, resolveDomain),
  filterViewable. Applied across routes: host mutations need manager on the
  host's domain; reads are filtered to visible domains; DNS providers, user
  management, and grant management are global-admin-only; certs need viewer.
- routes/grant.js: admin CRUD for grants. Anti-lockout via conf.auth.adminUsers
  plus migrations/grant_bootstrap.js.

Frontend: /me returns effective rights; nav gates Users/Grants to admins;
grants management page; OIDC token-fragment handling in app-base.js.

Tests: utils/roles and utils/oidc unit-tested (no redis); wired into the test
scripts. Full suite 89 pass. Also verified end-to-end against redis (grant
resolution, middleware allow/deny/403, list filtering) and the OIDC pure flow.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

nodejs/models/token.js

@@ -33,13 +33,31 @@ class AuthToken extends Token{
 	static _keyMap = {
 		...super._keyMap,
 		user: {model: 'User', rel: 'one', localKey: 'created_by'},
+		// Group memberships captured at login (OIDC `groups` claim or LDAP
+		// group membership), stored as a JSON string. Drives authorization for
+		// the life of the session without re-querying the IdP on every request.
+		groups: {default: '[]', isRequired: false, type: 'string'},
 	}
 
 	static async create(data){
 		data.created_by = data.username;
+		if(Array.isArray(data.groups)){
+			data.groups = JSON.stringify(data.groups);
+		}
 		return super.create(data)
 
 	}
+
+	// Parse the stored groups JSON back into an array, tolerating bad/missing
+	// data so authorization never crashes on a malformed token.
+	groupsArray(){
+		try{
+			let parsed = JSON.parse(this.groups);
+			return Array.isArray(parsed) ? parsed : [];
+		}catch(error){
+			return [];
+		}
+	}
 }
 AuthToken.register();