feat(ocr): extract translateOcrProgress with ANALYZING_PAGE and DONE:skipped support

Move translateOcrProgress from page.svelte to a testable module.
Return structured result with currentPage/totalPages/skippedPages
for the progress bar. Add ANALYZING_PAGE and DONE with skipped pages
parsing. Add i18n keys for de/en/es.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/lib/ocr/translateOcrProgress.ts

@@ -0,0 +1,56 @@
+import { m } from '$lib/paraglide/messages.js';
+
+export interface OcrProgressResult {
+	message: string;
+	currentPage?: number;
+	totalPages?: number;
+	skippedPages?: number;
+}
+
+export function translateOcrProgress(code: string): OcrProgressResult {
+	if (!code) return { message: m.ocr_progress_heading() };
+
+	const parts = code.split(':');
+	const key = parts[0];
+
+	switch (key) {
+		case 'PREPARING':
+			return { message: m.ocr_status_preparing() };
+		case 'LOADING':
+			return { message: m.ocr_status_loading() };
+		case 'ANALYZING':
+			return { message: m.ocr_status_analyzing() };
+		case 'CREATING_BLOCKS':
+			return { message: m.ocr_status_creating_blocks({ count: parts[1] ?? '0' }) };
+		case 'DONE': {
+			const count = parts[1] ?? '0';
+			const skipped = parts[2] ? parseInt(parts[2], 10) : 0;
+			if (skipped > 0) {
+				return {
+					message: m.ocr_status_done_skipped({
+						count,
+						skipped: String(skipped)
+					}),
+					skippedPages: skipped
+				};
+			}
+			return { message: m.ocr_status_done_blocks({ count }) };
+		}
+		case 'ANALYZING_PAGE': {
+			const current = parseInt(parts[1] ?? '0', 10);
+			const total = parseInt(parts[2] ?? '0', 10);
+			return {
+				message: m.ocr_status_analyzing_page({
+					current: String(current),
+					total: String(total)
+				}),
+				currentPage: current,
+				totalPages: total
+			};
+		}
+		case 'ERROR':
+			return { message: m.ocr_status_error() };
+		default:
+			return { message: code };
+	}
+}