fix: enforce read-only restrictions for viewer role across 5 pages

Audit and fix viewer (read-only) user permissions:
- Dashboard: hide health score refresh buttons
- Accounts: hide investment edit icons
- Invoices: hide Apply Late Fees and Generate Invoices buttons
- Capital Planning: disable drag-and-drop, hide grip handles and edit buttons
- Investment Planning: hide AI Recommendations refresh button

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

frontend/src/pages/capital-projects/CapitalProjectsPage.tsx

@@ -72,9 +72,10 @@ interface KanbanCardProps {
   project: Project;
   onEdit: (p: Project) => void;
   onDragStart: (e: DragEvent<HTMLDivElement>, project: Project) => void;
+  isReadOnly?: boolean;
 }
 
-function KanbanCard({ project, onEdit, onDragStart }: KanbanCardProps) {
+function KanbanCard({ project, onEdit, onDragStart, isReadOnly }: KanbanCardProps) {
   const plannedLabel = formatPlannedDate(project.planned_date);
   // For projects in the Future bucket with a specific year, show the year
   const currentYear = new Date().getFullYear();
@@ -86,21 +87,23 @@ function KanbanCard({ project, onEdit, onDragStart }: KanbanCardProps) {
       padding="sm"
       radius="md"
       withBorder
-      draggable
-      onDragStart={(e) => onDragStart(e, project)}
-      style={{ cursor: 'grab', userSelect: 'none' }}
+      draggable={!isReadOnly}
+      onDragStart={!isReadOnly ? (e) => onDragStart(e, project) : undefined}
+      style={{ cursor: isReadOnly ? 'default' : 'grab', userSelect: 'none' }}
       mb="xs"
     >
       <Group justify="space-between" wrap="nowrap" mb={4}>
         <Group gap={6} wrap="nowrap" style={{ overflow: 'hidden' }}>
-          <IconGripVertical size={14} style={{ flexShrink: 0, color: 'var(--mantine-color-dimmed)' }} />
+          {!isReadOnly && <IconGripVertical size={14} style={{ flexShrink: 0, color: 'var(--mantine-color-dimmed)' }} />}
           <Text fw={600} size="sm" truncate>
             {project.name}
           </Text>
         </Group>
-        <ActionIcon variant="subtle" size="sm" onClick={() => onEdit(project)}>
-          <IconEdit size={14} />
-        </ActionIcon>
+        {!isReadOnly && (
+          <ActionIcon variant="subtle" size="sm" onClick={() => onEdit(project)}>
+            <IconEdit size={14} />
+          </ActionIcon>
+        )}
       </Group>
 
       <Group gap={6} mb={6}>
@@ -148,11 +151,12 @@ interface KanbanColumnProps {
   isDragOver: boolean;
   onDragOverHandler: (e: DragEvent<HTMLDivElement>, year: number) => void;
   onDragLeave: () => void;
+  isReadOnly?: boolean;
 }
 
 function KanbanColumn({
   year, projects, onEdit, onDragStart, onDrop,
-  isDragOver, onDragOverHandler, onDragLeave,
+  isDragOver, onDragOverHandler, onDragLeave, isReadOnly,
 }: KanbanColumnProps) {
   const totalEst = projects.reduce((s, p) => s + parseFloat(p.estimated_cost || '0'), 0);
   const isFuture = year === FUTURE_YEAR;
@@ -178,9 +182,9 @@ function KanbanColumn({
         border: isDragOver ? '2px dashed var(--mantine-color-blue-4)' : undefined,
         transition: 'background-color 150ms ease, border 150ms ease',
       }}
-      onDragOver={(e) => onDragOverHandler(e, year)}
-      onDragLeave={onDragLeave}
-      onDrop={(e) => onDrop(e, year)}
+      onDragOver={!isReadOnly ? (e) => onDragOverHandler(e, year) : undefined}
+      onDragLeave={!isReadOnly ? onDragLeave : undefined}
+      onDrop={!isReadOnly ? (e) => onDrop(e, year) : undefined}
     >
       <Group justify="space-between" mb="sm">
         <Title order={5}>{yearLabel(year)}</Title>
@@ -199,7 +203,7 @@ function KanbanColumn({
       <Box style={{ flex: 1, minHeight: 60 }}>
         {projects.length === 0 ? (
           <Text size="xs" c="dimmed" ta="center" py="lg">
-            Drop projects here
+            {isReadOnly ? 'No projects' : 'Drop projects here'}
           </Text>
         ) : useWideLayout ? (
           <div style={{
@@ -208,12 +212,12 @@ function KanbanColumn({
             gap: 'var(--mantine-spacing-xs)',
           }}>
             {projects.map((p) => (
-              <KanbanCard key={p.id} project={p} onEdit={onEdit} onDragStart={onDragStart} />
+              <KanbanCard key={p.id} project={p} onEdit={onEdit} onDragStart={onDragStart} isReadOnly={isReadOnly} />
             ))}
           </div>
         ) : (
           projects.map((p) => (
-            <KanbanCard key={p.id} project={p} onEdit={onEdit} onDragStart={onDragStart} />
+            <KanbanCard key={p.id} project={p} onEdit={onEdit} onDragStart={onDragStart} isReadOnly={isReadOnly} />
           ))
         )}
       </Box>
@@ -595,6 +599,7 @@ export function CapitalProjectsPage() {
               isDragOver={dragOverYear === year}
               onDragOverHandler={handleDragOver}
               onDragLeave={handleDragLeave}
+              isReadOnly={isReadOnly}
             />
           );
         })}