fix(sign): prevent custom workbench auto-revert when opening sign editor

`unregisterCustomWorkbenchView` depended on `[actions]` from
NavigationContext. Because `actions` gets a new reference every time
`workbench` changes (setWorkbench captures state.workbench in its
closure), the registration effect in CombinedSign re-ran on each
workbench update, firing cleanup → clearCustomWorkbenchViewData →
auto-revert effect reverted the workbench back to default.

Fix: introduce `actionsRef` (updated each render, stable identity) and
use it in `unregisterCustomWorkbenchView` (now has empty dep array) and
the auto-revert effect (removes `actions` from deps). Also cleaned up
diagnostic console.log calls added during debugging.

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

frontend/src/core/contexts/NavigationContext.tsx

@@ -114,12 +114,6 @@ export const NavigationProvider: React.FC<{
   const setWorkbench = useCallback((workbench: WorkbenchType) => {
       // Check for unsaved changes using registered checker or state
       const hasUnsavedChanges = unsavedChangesCheckerRef.current?.() || state.hasUnsavedChanges;
-      console.log('[NavigationContext] setWorkbench:', {
-        from: state.workbench,
-        to: workbench,
-        hasChecker: !!unsavedChangesCheckerRef.current,
-        hasUnsavedChanges
-      });
 
       // If we're leaving pageEditor, viewer, or custom workbench and have unsaved changes, request navigation
       const leavingWorkbenchWithChanges =
@@ -134,16 +128,9 @@ export const NavigationProvider: React.FC<{
         }
         const performWorkbenchChange = () => {
           // When leaving a custom workbench, clear the selected tool
-          console.log('[NavigationContext] performWorkbenchChange executing', {
-            from: state.workbench,
-            to: workbench,
-            isCustom: state.workbench.startsWith('custom:')
-          });
           if (state.workbench.startsWith('custom:')) {
-            console.log('[NavigationContext] Clearing tool and changing workbench to:', workbench);
             dispatch({ type: 'SET_TOOL_AND_WORKBENCH', payload: { toolId: null, workbench } });
           } else {
-            console.log('[NavigationContext] Just changing workbench to:', workbench);
             dispatch({ type: 'SET_WORKBENCH', payload: { workbench } });
           }
         };
@@ -206,19 +193,13 @@ export const NavigationProvider: React.FC<{
     }, [state.hasUnsavedChanges]);
 
     const confirmNavigation = useCallback(() => {
-      console.log('[NavigationContext] confirmNavigation called', {
-        hasPendingNav: !!state.pendingNavigation,
-        currentWorkbench: state.workbench,
-        currentTool: state.selectedTool
-      });
       if (state.pendingNavigation) {
         state.pendingNavigation();
       }
 
       dispatch({ type: 'SET_PENDING_NAVIGATION', payload: { navigationFn: null } });
       dispatch({ type: 'SHOW_NAVIGATION_WARNING', payload: { show: false } });
-      console.log('[NavigationContext] confirmNavigation completed');
-    }, [state.pendingNavigation, state.workbench, state.selectedTool]);
+    }, [state.pendingNavigation]);
 
     const cancelNavigation = useCallback(() => {
       dispatch({ type: 'SET_PENDING_NAVIGATION', payload: { navigationFn: null } });

frontend/src/core/contexts/ToolWorkflowContext.tsx

@@ -3,7 +3,7 @@
  * Eliminates prop drilling with a single, simple context
  */
 
-import React, { createContext, useContext, useReducer, useCallback, useMemo, useEffect } from 'react';
+import React, { createContext, useContext, useReducer, useCallback, useMemo, useEffect, useRef } from 'react';
 import { useToolManagement, type ToolAvailabilityMap } from '@app/hooks/useToolManagement';
 import { PageEditorFunctions } from '@app/types/pageEditor';
 import { ToolRegistryEntry, ToolRegistry } from '@app/data/toolsTaxonomy';
@@ -117,6 +117,12 @@ export function ToolWorkflowProvider({ children }: ToolWorkflowProviderProps) {
   // Navigation actions and state are available since we're inside NavigationProvider
   const { actions } = useNavigationActions();
   const navigationState = useNavigationState();
+  const workbenchRef = useRef(navigationState.workbench);
+  const actionsRef = useRef(actions);
+  useEffect(() => {
+    workbenchRef.current = navigationState.workbench;
+    actionsRef.current = actions;
+  });
 
   // Tool management hook
   const { toolRegistry, getSelectedTool, toolAvailability } = useToolManagement();
@@ -198,10 +204,10 @@ export function ToolWorkflowProvider({ children }: ToolWorkflowProviderProps) {
       return updated;
     });
 
-    if (removedView && navigationState.workbench === removedView.workbenchId) {
-      actions.setWorkbench(getDefaultWorkbench());
+    if (removedView && workbenchRef.current === removedView.workbenchId) {
+      actionsRef.current.setWorkbench(getDefaultWorkbench());
     }
-  }, [actions, navigationState.workbench]);
+  }, []); // stable — uses refs for mutable values
 
   const setCustomWorkbenchViewData = useCallback((id: string, dataOrUpdater: any | ((prev: any) => any)) => {
     setCustomViewData(prev => {
@@ -242,9 +248,9 @@ export function ToolWorkflowProvider({ children }: ToolWorkflowProviderProps) {
 
     const currentCustomView = customWorkbenchViews.find(view => view.workbenchId === navigationState.workbench);
     if (!currentCustomView || currentCustomView.data == null) {
-      actions.setWorkbench(getDefaultWorkbench());
+      actionsRef.current.setWorkbench(getDefaultWorkbench());
     }
-  }, [actions, customWorkbenchViews, navigationState.workbench, navigationState.pendingNavigation, navigationState.showNavigationWarning]);
+  }, [customWorkbenchViews, navigationState.workbench, navigationState.pendingNavigation, navigationState.showNavigationWarning]);
 
   // Persisted via PreferencesContext; no direct localStorage writes needed here