feat(ts): R4 TypeScript hardening H1-H6 — reduce errors 177→152

H1: CCGraphNavPanel — useMemo import + LogCategory fix
H2: CCTimetableLessonNodeShapeUtil — props type alignment (cc-graph-props.ts)
H3: cc-graph-shapes — add missing CCTimetableLessonNode* import (was never imported)
H4: CCNodeSnapshotPanel — RestartAlt import from @mui/icons-material
H5: CCExamMarkerPanel + CCFilesPanelEnhanced — BlobPart cast + webkitdirectory @ts-ignore
H6: TranscriptionManager — setTranscriptionCallback interface fix
Plus: CCExportPdfButton BlobPart cast, SimpleUploadTest icon imports, graph-sidebar LogCategory

tsc before: 177 (master)
tsc after:  152 (reduction of 25 errors, well below 160 acceptable threshold)

src/utils/tldraw/ui-overrides/components/shared/CCExamMarkerPanel.tsx

@@ -200,7 +200,7 @@ export const CCExamMarkerPanel: React.FC<CCExamMarkerPanelProps> = ({
 
     const pdfBytes = await newPdf.save();
     const url = URL.createObjectURL(
-      new Blob([pdfBytes], { type: 'application/pdf' })
+      new Blob([pdfBytes] as unknown as BlobPart[], { type: 'application/pdf' })
     );
     tickProgress();
 
@@ -297,7 +297,7 @@ export const CCExamMarkerPanel: React.FC<CCExamMarkerPanelProps> = ({
 
         // Save the combined PDF
         const pdfBytes = await newPdf.save();
-        const url = URL.createObjectURL(new Blob([pdfBytes], { type: 'application/pdf' }));
+        const url = URL.createObjectURL(new Blob([pdfBytes] as unknown as BlobPart[], { type: 'application/pdf' }));
         const a = document.createElement('a');
         a.href = url;
         a.download = currentPdf.name;

src/utils/tldraw/ui-overrides/components/shared/CCFilesPanelEnhanced.tsx

@@ -346,9 +346,10 @@ export const CCFilesPanelEnhanced: React.FC = () => {
             ref={dirInputRef}
             type="file" 
             style={{ display: 'none' }} 
-            webkitdirectory="" 
-            multiple 
+            multiple
             onChange={handleFallbackDirectorySelect}
+            // @ts-ignore WebKit directory picker attribute for folder upload
+            webkitdirectory=""
           />
           
           <Tooltip title={isDirectoryPickerSupported() ? "Uses modern directory picker" : "Uses fallback method"}>

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

@@ -1,4 +1,4 @@
-import React, { useState, useEffect, useCallback, createContext, useContext } from 'react';
+import React, { useState, useEffect, useCallback, createContext, useContext, useMemo } from 'react';
 import {
     Box, IconButton, CircularProgress, Collapse, Typography, Tooltip,
     ToggleButtonGroup, ToggleButton,
@@ -518,7 +518,7 @@ export function CCGraphNavPanel() {
             const data = await res.json();
             setTree(data.tree);
         } catch (err) {
-            logger.error('graph-nav-panel', 'Failed to load graph tree', err);
+            logger.error('navigation-panel', 'Failed to load graph tree', err);
             setError('Failed to load navigation tree');
         } finally {
             setLoading(false);
@@ -650,12 +650,12 @@ export function CCGraphNavPanel() {
     }, []);
 
     const handleCalendarWizardComplete = useCallback(() => {
-        logger.info('graph-nav-panel', 'School calendar setup complete');
+        logger.info('navigation-panel', 'School calendar setup complete');
         refreshAll();
     }, [refreshAll]);
 
     const handleTimetableWizardComplete = useCallback((timetableId: string) => {
-        logger.info('graph-nav-panel', 'Teacher timetable setup complete', { timetableId });
+        logger.info('navigation-panel', 'Teacher timetable setup complete', { timetableId });
         refreshAll();
     }, [refreshAll]);
 

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

@@ -1,7 +1,7 @@
 import React, { useCallback, useMemo, useState } from 'react';
 import { Box, Typography, styled, Button, ThemeProvider, createTheme, useMediaQuery } from '@mui/material';
 import Save from '@mui/icons-material/Save';
-import Reset from '@mui/icons-material/RestartAlt';
+import { RestartAlt } from '@mui/icons-material';
 import { useEditor, useToasts, loadSnapshot } from '@tldraw/tldraw';
 import { useNavigationStore } from '../../../../../../stores/navigationStore';
 import { useAuth } from '../../../../../../contexts/AuthContext';