refactor: move shared utilities to lib/shared/ sub-packages

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

frontend/src/lib/ocr/training.ts

@@ -0,0 +1,13 @@
+export interface TrainingRun {
+	id: string;
+	status: 'QUEUED' | 'RUNNING' | 'DONE' | 'FAILED';
+	personId?: string;
+	blockCount: number;
+	documentCount: number;
+	modelName: string;
+	errorMessage?: string;
+	triggeredBy?: string;
+	createdAt: string;
+	completedAt?: string;
+	cer?: number;
+}