feat(document-page): auto-open transcription panel when ?task=transcribe is present

On mount, reads the task query param before the comment deep-link handler.
When task=transcribe, opens the transcription panel, scrolls the close button
into view, moves focus to it, then strips the param from the URL via replaceState.

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

frontend/src/lib/components/SegmentationColumn.svelte

@@ -36,7 +36,7 @@ let { docs, weeklyCount }: Props = $props();
 			{#each docs as doc (doc.id)}
 				<li>
 					<a
-						href="/documents/{doc.id}"
+						href="/documents/{doc.id}?task=transcribe"
 						class="flex min-h-[44px] flex-col justify-center rounded px-1 py-2 hover:bg-canvas focus-visible:ring-2 focus-visible:ring-focus-ring focus-visible:ring-offset-2 focus-visible:outline-none"
 					>
 						<span class="font-serif text-sm text-ink">{doc.title}</span>

frontend/src/lib/components/SegmentationColumn.svelte.spec.ts

@@ -56,12 +56,12 @@ describe('SegmentationColumn', () => {
 		await expect.element(page.getByText(/diese Woche/)).not.toBeInTheDocument();
 	});
 
-	it('links to /documents/{id}', async () => {
+	it('links to /documents/{id}?task=transcribe', async () => {
 		const doc = makeDoc({ id: 'abc-123', title: 'Verlinktes Dokument' });
 
 		render(SegmentationColumn, { props: { docs: [doc], weeklyCount: 0 } });
 
 		const link = page.getByRole('link', { name: /Verlinktes Dokument/ });
-		await expect.element(link).toHaveAttribute('href', '/documents/abc-123');
+		await expect.element(link).toHaveAttribute('href', '/documents/abc-123?task=transcribe');
 	});
 });

frontend/src/lib/components/TranscriptionColumn.svelte

@@ -41,7 +41,7 @@ function blockProgress(doc: TranscriptionQueueItemDTO): number {
 			{#each docs as doc (doc.id)}
 				<li>
 					<a
-						href="/documents/{doc.id}"
+						href="/documents/{doc.id}?task=transcribe"
 						class="flex min-h-[44px] flex-col justify-center rounded px-1 py-2 hover:bg-canvas focus-visible:ring-2 focus-visible:ring-focus-ring focus-visible:ring-offset-2 focus-visible:outline-none"
 					>
 						<span class="font-serif text-sm text-ink">{doc.title}</span>

frontend/src/lib/components/TranscriptionColumn.svelte.spec.ts

@@ -74,12 +74,12 @@ describe('TranscriptionColumn', () => {
 		expect(dashEl?.textContent?.trim()).toBe('—');
 	});
 
-	it('links to /documents/{id}', async () => {
+	it('links to /documents/{id}?task=transcribe', async () => {
 		const doc = makeDoc({ id: 'xyz-456', title: 'Transkriptions Dokument' });
 
 		render(TranscriptionColumn, { props: { docs: [doc], weeklyCount: 0 } });
 
 		const link = page.getByRole('link', { name: /Transkriptions Dokument/ });
-		await expect.element(link).toHaveAttribute('href', '/documents/xyz-456');
+		await expect.element(link).toHaveAttribute('href', '/documents/xyz-456?task=transcribe');
 	});
 });

frontend/src/routes/documents/[id]/+page.svelte

@@ -362,6 +362,19 @@ onMount(() => {
 		);
 	}
 
+	if (page.url.searchParams.get('task') === 'transcribe') {
+		transcribeMode = true;
+		tick().then(() => {
+			const closeBtn = document.querySelector<HTMLElement>('[data-testid="panel-close"]');
+			closeBtn?.scrollIntoView({
+				behavior: prefersReducedMotion ? 'instant' : 'smooth',
+				block: 'nearest'
+			});
+			closeBtn?.focus({ preventScroll: true });
+			replaceState(page.url.pathname, page.state ?? {});
+		});
+	}
+
 	scrollToCommentFromQuery(new URL(page.url), {
 		transcribeMode,
 		setTranscribeMode: (v) => (transcribeMode = v),