fix: grant admin role to anonymous user and add DEFAULT_TOOL_VIEW env var

When AUTH_ENABLED=false, the anonymous user was assigned the "user" role
which lacks settings:write permission, making all settings saves return
403. Since no admin exists when auth is disabled, settings were
permanently read-only. Promote the anonymous user to "admin" so the
single user has full control of the instance.

Also adds DEFAULT_TOOL_VIEW env var (sidebar|fullscreen) following the
existing DEFAULT_THEME pattern, seeded via ensureDefaultSettings() on
first boot.

Closes #135

apps/web/src/hooks/use-auth.ts

@@ -18,12 +18,21 @@ interface AuthState {
   hasLocalPassword: boolean;
 }
 
-const USER_PERMISSIONS = [
+const ANON_ADMIN_PERMISSIONS = [
   "tools:use",
   "files:own",
+  "files:all",
   "apikeys:own",
+  "apikeys:all",
   "pipelines:own",
+  "pipelines:all",
   "settings:read",
+  "settings:write",
+  "users:manage",
+  "teams:manage",
+  "features:manage",
+  "system:health",
+  "audit:read",
 ];
 
 export function useAuth() {
@@ -58,8 +67,8 @@ export function useAuth() {
               authEnabled: false,
               isAuthenticated: true,
               mustChangePassword: false,
-              role: "user",
-              permissions: USER_PERMISSIONS,
+              role: "admin",
+              permissions: ANON_ADMIN_PERMISSIONS,
               analyticsEnabled: null,
               analyticsConsentShownAt: null,
               analyticsConsentRemindAt: null,