Add control logic engine, panel logic dialogs, logic-edit restriction

Introduce server-side control-logic flow graphs (cron/alarm triggers,
Lua blocks) with CRUD endpoints, panel-logic lifecycle triggers and
user-interaction dialog nodes, and a synthetic node-graph editor.

Add an optional logic-editor allowlist (server.logic_editors) gating who
may add/edit panel logic and control logic, surfaced via /api/v1/me and
enforced in the API; hide logic affordances in the UI accordingly.

Update README, example config, and functional/technical specs to cover
all current features (plot panels, panel/control logic, local variables,
access control) and refresh the in-app manual and contextual help.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/ViewMode.tsx

@@ -10,6 +10,7 @@ import type { Interface } from './lib/types';
 import ContextualHelp from './ContextualHelp';
 import HelpModal from './HelpModal';
 import ZoomControl from './ZoomControl';
+import ControlLogicEditor from './ControlLogicEditor';
 
 interface Props {
   onEdit?: (iface?: Interface) => void;
@@ -31,6 +32,7 @@ export default function ViewMode({ onEdit, initialInterface, onView }: Props) {
   const [showHelp, setShowHelp] = useState(false);
   const [helpSection, setHelpSection] = useState('start');
   const [showTimeNav, setShowTimeNav] = useState(false);
+  const [showControlLogic, setShowControlLogic] = useState(false);
   const [leftW, setLeftW] = useState(220);
   const [listCollapsed, setListCollapsed] = useState(false);
   const me = useAuth();
@@ -155,6 +157,15 @@ export default function ViewMode({ onEdit, initialInterface, onView }: Props) {
             📖
           </button>
           <ZoomControl />
+          {writable && me.canEditLogic && (
+            <button
+              class="toolbar-btn"
+              onClick={() => setShowControlLogic(true)}
+              title="Open server-side control logic"
+            >
+              ⚙ Control logic
+            </button>
+          )}
           {writable && (
             <button
               class="btn-edit"
@@ -242,6 +253,10 @@ export default function ViewMode({ onEdit, initialInterface, onView }: Props) {
       {showHelp && (
         <HelpModal initialSection={helpSection} onClose={() => setShowHelp(false)} />
       )}
+
+      {showControlLogic && (
+        <ControlLogicEditor onClose={() => setShowControlLogic(false)} />
+      )}
     </div>
   );
 }