feat(nav): add launch buttons for My Timetable and My Classes sections

Add useNavigate + Launch icon to TreeItem; timetable section shows a
launch button routing to /my-lessons, classes section routes to /my-classes.
Both buttons only appear when the section status is populated.
Exclude classes section from the unlinked/pending icon fallback.

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

src/utils/tldraw/ui-overrides/components/shared/navigation/CCGraphNavPanel.tsx

@@ -19,7 +19,9 @@ import {
     GridOn as GridIcon,
     Settings as SetupIcon,
     Edit as EditIcon,
+    Launch as LaunchIcon,
 } from '@mui/icons-material';
+import { useNavigate } from 'react-router-dom';
 import { useNavigationStore } from '../../../../../../stores/navigationStore';
 import { useAuth } from '../../../../../../contexts/AuthContext';
 import { NeoGraphNode } from '../../../../../../types/navigation';
@@ -124,6 +126,7 @@ interface TreeItemProps {
 
 function TreeItem({ node, depth, onSelect, onExpand }: TreeItemProps) {
     const ctx = useContext(NavPanelContext);
+    const navigate = useNavigate();
     const [expanded, setExpanded] = useState(node.is_section && node.status === 'populated');
     const [children, setChildren] = useState<TreeNode[]>(node.children || []);
     const [loading, setLoading] = useState(false);
@@ -132,6 +135,7 @@ function TreeItem({ node, depth, onSelect, onExpand }: TreeItemProps) {
     const isCalendarSection = isSection && node.section_id === 'calendar';
     const isTimetableSection = isSection && node.section_id === 'timetable';
     const isSchoolSection = isSection && node.section_id === 'school';
+    const isClassesSection = isSection && node.section_id === 'classes';
     const SectionIcon = node.section_id ? SECTION_ICONS[node.section_id] : null;
     const Icon = SectionIcon || NODE_ICONS[node.node_type] || HomeIcon;
 
@@ -196,6 +200,8 @@ function TreeItem({ node, depth, onSelect, onExpand }: TreeItemProps) {
     const showLegacySetup = isTimetableSection && node.status === 'empty' && !ss;
     const showTimetableEdit = isTimetableSection && node.status === 'populated'
         && ss && ss.status !== 'no_school' && !!ss.teacher_has_timetable;
+    const showTimetableView = isTimetableSection && node.status === 'populated';
+    const showClassesView = isClassesSection && node.status === 'populated';
 
     if (isSection) {
         return (
@@ -223,7 +229,7 @@ function TreeItem({ node, depth, onSelect, onExpand }: TreeItemProps) {
                                     </IconButton>
                                 )
                         )}
-                        {isEmpty && !isCalendarSection && !isTimetableSection && !isSchoolSection && (
+                        {isEmpty && !isCalendarSection && !isTimetableSection && !isSchoolSection && !isClassesSection && (
                             <Box sx={{ width: 18, display: 'flex', alignItems: 'center', justifyContent: 'center' }}>
                                 {node.status === 'no_school'
                                     ? <UnlinkedIcon sx={{ fontSize: 11, color: 'text.disabled' }} />
@@ -249,7 +255,7 @@ function TreeItem({ node, depth, onSelect, onExpand }: TreeItemProps) {
                         {node.label}
                     </Typography>
 
-                    {isEmpty && !isCalendarSection && !isTimetableSection && !isSchoolSection && node.status && (
+                    {isEmpty && !isCalendarSection && !isTimetableSection && !isSchoolSection && !isClassesSection && node.status && (
                         <Tooltip title={STATUS_MESSAGES[node.status]} placement="right">
                             <Typography variant="caption" sx={{ fontSize: '0.6rem', color: 'text.disabled', ml: 0.5, flexShrink: 0 }}>
                                 {node.status === 'no_school' ? '—' : '…'}
@@ -319,6 +325,28 @@ function TreeItem({ node, depth, onSelect, onExpand }: TreeItemProps) {
                             </IconButton>
                         </Tooltip>
                     )}
+                    {showTimetableView && (
+                        <Tooltip title="View as lesson list" placement="right">
+                            <IconButton
+                                size="small"
+                                sx={{ p: 0.25, ml: 0.5, color: 'text.secondary' }}
+                                onClick={e => { e.stopPropagation(); navigate('/my-lessons'); }}
+                            >
+                                <LaunchIcon sx={{ fontSize: 13 }} />
+                            </IconButton>
+                        </Tooltip>
+                    )}
+                    {showClassesView && (
+                        <Tooltip title="View my classes" placement="right">
+                            <IconButton
+                                size="small"
+                                sx={{ p: 0.25, ml: 0.5, color: 'text.secondary' }}
+                                onClick={e => { e.stopPropagation(); navigate('/my-classes'); }}
+                            >
+                                <LaunchIcon sx={{ fontSize: 13 }} />
+                            </IconButton>
+                        </Tooltip>
+                    )}
                 </Box>
 
                 {/* Calendar mode toggle */}