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/cc-base/cc-transcription/TranscriptionManager.ts

@@ -27,8 +27,8 @@ export class TranscriptionManager {
     this.transcriptionService = new TranscriptionService();
 
     // Set up callback for transcription updates
-    this.transcriptionService.setTranscriptionCallback((text: string, isFinal: boolean, metadata: { start: number, end: number }) => {
-      console.log('📝 Transcription update received:', { text, metadata });
+    this.transcriptionService.setServerSegmentsCallback((segments: Array<{ text: string; start: number; end: number }>, isLastLive: boolean) => {
+      console.log('📝 Transcription update received:', { segments: segments.length, isLastLive });
       const util = this.editor.getShapeUtil<CCLiveTranscriptionShapeUtil>('cc-live-transcription');
       if (!util) {
         console.warn('❌ Shape util not found');
@@ -36,6 +36,10 @@ export class TranscriptionManager {
       }
       console.log('Found transcription util:', !!util);
 
+      const text = segments.map(s => s.text).join('') || '';
+      const metadata = segments.length ? { start: segments[0].start, end: segments[segments.length - 1].end } : { start: 0, end: 0 };
+      const isFinal = isLastLive;
+
       // Check if text is stable (same output multiple times)
       const isStable = text === this.lastText;
       if (isStable) {