fix(tests): fix 13 pre-existing vitest-browser spec failures

Fixes all remaining failing tests in the browser project. Root cause in
every case: Playwright CDP-based clicks/keyboard events do not reliably
trigger Svelte 5 onclick/onkeydown handlers. Pattern applied throughout:

- Buttons / result items: native `.element().click()` or
  `dispatchEvent(new MouseEvent('click', { bubbles: true }))`
- Keyboard events: `dispatchEvent(new KeyboardEvent('keydown', { key }))`
  on the target DOM element
- TipTap selection: `element.focus()` + Selection API +
  `document.dispatchEvent(new Event('selectionchange'))`
- ProseMirror focus for onFocus: `dispatchEvent(new FocusEvent('focus'))`

Also fixes pre-existing content/logic issues found during analysis:
- ChronikErrorCard, BulkDropZone, CorrespondenzHero: stale i18n strings
  and wrong ARIA role (combobox not textbox)
- RichtlinienRuleCard: beide beispielInput + beispielOutput required for
  arrow to render; querySelectorAll to get last code element
- admin/system/page: vi.unstubAllGlobals() in afterEach; strict-mode
  heading selector; per-call mockResolvedValueOnce for dual-card page
- DocumentList: add total prop + result count paragraph (test relied on it)
- PersonTypeahead keyboard navigation: pressKey() helper with native
  KeyboardEvent dispatch replaces userEvent.keyboard()
- PersonMultiSelect: native element clicks for result selection and
  chip removal; keydown dispatch on result div for Enter key test

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

frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts

@@ -174,7 +174,14 @@ describe('PersonMentionEditor — AC-1: typed text as displayName', () => {
 			await expect.element(page.getByRole('option', { name: /Auguste Raddatz/ })).toBeVisible();
 		});
 
-		await userEvent.click(page.getByRole('option', { name: /Auguste Raddatz/ }));
+		// MentionDropdown handles selection via onmousedown (not onclick) to prevent
+		// blurring the editor before the selection fires.  userEvent.click() via CDP
+		// does not reliably trigger Svelte 5's onmousedown handler when TipTap is
+		// mounted — dispatch the MouseEvent directly from browser JS instead.
+		const option = (await page
+			.getByRole('option', { name: /Auguste Raddatz/ })
+			.element()) as HTMLElement;
+		option.dispatchEvent(new MouseEvent('mousedown', { bubbles: true, cancelable: true }));
 
 		await vi.waitFor(() => {
 			expect(host.snapshot.mentionedPersons).toHaveLength(1);
@@ -212,7 +219,10 @@ describe('PersonMentionEditor — AC-1: typed text as displayName', () => {
 			await expect.element(page.getByRole('option', { name: /Auguste Raddatz/ })).toBeVisible();
 		});
 
-		await userEvent.click(page.getByRole('option', { name: /Auguste Raddatz/ }));
+		const option = (await page
+			.getByRole('option', { name: /Auguste Raddatz/ })
+			.element()) as HTMLElement;
+		option.dispatchEvent(new MouseEvent('mousedown', { bubbles: true, cancelable: true }));
 
 		await vi.waitFor(() => {
 			expect(host.snapshot.mentionedPersons).toEqual([{ personId: 'p-aug', displayName: 'Aug' }]);

frontend/src/lib/shared/primitives/RichtlinienRuleCard.svelte.spec.ts

@@ -9,6 +9,8 @@ const defaultProps = {
 	icon: '✍',
 	title: 'Unleserliche Wörter',
 	body: 'Schreiben Sie [unleserlich].',
+	// beispielInput is required for the → arrow to render (component: {#if beispielInput !== undefined})
+	beispielInput: '[Original]',
 	beispielOutput: '[unleserlich]'
 };
 
@@ -34,9 +36,12 @@ describe('RichtlinienRuleCard', () => {
 
 	it('renders beispielOutput in monospace with → arrow', async () => {
 		render(RichtlinienRuleCard, { props: defaultProps });
-		const mono = document.querySelector('code, [class*="font-mono"]');
-		expect(mono).not.toBeNull();
-		expect(mono!.textContent).toContain('[unleserlich]');
+		// With both beispielInput and beispielOutput, the component renders two code elements:
+		// [Input] → [Output]. querySelectorAll gets both; last one is the output.
+		const codes = document.querySelectorAll('code, [class*="font-mono"]');
+		expect(codes.length).toBeGreaterThanOrEqual(1);
+		const outputCode = codes[codes.length - 1];
+		expect(outputCode.textContent).toContain('[unleserlich]');
 		await expect.element(page.getByText(/→/)).toBeInTheDocument();
 	});