feat(document): drop the read-only Originaltext field from the edit form

The "Originaltext:" line in WhoWhenSection rendered the verbatim import
cell (metaDateRaw) as static text plus a hidden input that re-submitted
it on every save. Editors mistook it for an editable field. Remove the
visible line, the hidden round-trip input, and the now-unused rawDate
prop (here and at the DocumentEditLayout call site). The backend's
partial update preserves the stored value, so no data is lost.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/lib/document/DocumentEditLayout.svelte

@@ -209,7 +209,6 @@ async function handleReplaceFile(e: Event) {
 					bind:dateIso={dateIso}
 					bind:precision={datePrecision}
 					bind:endDateIso={dateEndIso}
-					rawDate={doc.metaDateRaw ?? ''}
 					initialDateIso={doc.documentDate ?? ''}
 					initialLocation={doc.location ?? ''}
 					initialSenderName={doc.sender?.displayName ?? ''}

frontend/src/lib/document/WhoWhenSection.svelte

@@ -16,7 +16,6 @@ let {
 	dateIso = $bindable(''),
 	precision = $bindable<DatePrecision>('DAY'),
 	endDateIso = $bindable(''),
-	rawDate = '',
 	initialDateIso = '',
 	initialLocation = '',
 	initialSenderName = '',
@@ -30,7 +29,6 @@ let {
 	dateIso?: string;
 	precision?: DatePrecision;
 	endDateIso?: string;
-	rawDate?: string;
 	initialDateIso?: string;
 	initialLocation?: string;
 	initialSenderName?: string;
@@ -179,15 +177,6 @@ $effect(() => {
 				{/if}
 			</div>
 			<input type="hidden" name="metaDateEnd" value={showEndDate ? endDateIso : ''} />
-
-			<!-- Originaltext (read-only raw cell): labelled static text, not a disabled input. -->
-			{#if rawDate && rawDate.trim().length > 0}
-				<div data-testid="who-when-raw">
-					<p class="mb-1 block text-sm font-medium text-ink-2">{m.date_original_label()}</p>
-					<p class="font-sans text-sm text-ink">{rawDate}</p>
-					<input type="hidden" name="metaDateRaw" value={rawDate} />
-				</div>
-			{/if}
 		{/if}
 
 		<!-- Absender (required in upload mode — row 1, col 2) -->

frontend/src/lib/document/WhoWhenSection.svelte.test.ts

@@ -93,13 +93,12 @@ describe('WhoWhenSection — precision controls', () => {
 		expect(document.querySelector('input#metaDateEnd')).not.toBeNull();
 	});
 
-	it('renders the raw cell as static text (not an editable input) and escapes it', async () => {
-		render(WhoWhenSection, { rawDate: '<b>Sommer</b> 1916' });
-		const raw = document.querySelector('[data-testid="who-when-raw"]');
-		expect(raw).not.toBeNull();
-		// Verbatim shown as escaped text; no injected <b> element.
-		expect(raw?.textContent).toContain('<b>Sommer</b> 1916');
-		expect(raw?.querySelector('b')).toBeNull();
+	it('never renders the raw cell, and never re-submits it via a hidden input', async () => {
+		render(WhoWhenSection, {});
+		// The confusing "Originaltext" line is gone …
+		expect(document.querySelector('[data-testid="who-when-raw"]')).toBeNull();
+		// … and editing no longer round-trips metaDateRaw to the backend.
+		expect(document.querySelector('input[name="metaDateRaw"]')).toBeNull();
 	});
 });