fix(#248): address PR review concerns — i18n, aria-label, stable keys, test selectors

- Add filter_operator_and/or/and_label/or_label i18n keys to de/en/es locale files
- Add aria-label and aria-pressed to AND/OR toggle buttons in SearchFilterBar
- Add data-testid="operator-and/or" for unambiguous test targeting (fixes substring match on German "Schlagwort")
- Use stable keys (tag.id ?? tag.name) for TagInput chip and suggestion lists
- Remove aria-level from role="option" items in TagInput (invalid attribute for that role)
- Add aria-live="polite" role="status" to TagMergeZone step indicator

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

frontend/messages/de.json

@@ -604,5 +604,9 @@
 	"admin_tag_delete_only_this_sub_root": "Untergeordnete werden zu Root-Schlagwörtern",
 	"admin_tag_delete_subtree": "Gesamten Teilbaum löschen",
 	"admin_tag_delete_subtree_warn": "Löscht auch {count} untergeordnete Schlagwörter",
-	"admin_tag_delete_confirm_heading": "Gib «{name}» zur Bestätigung ein:"
+	"admin_tag_delete_confirm_heading": "Gib «{name}» zur Bestätigung ein:",
+	"filter_operator_and": "UND",
+	"filter_operator_or": "ODER",
+	"filter_operator_and_label": "Alle gewählten Schlagworte müssen zutreffen (UND)",
+	"filter_operator_or_label": "Mindestens ein Schlagwort muss zutreffen (ODER)"
 }

frontend/messages/en.json

@@ -604,5 +604,9 @@
 	"admin_tag_delete_only_this_sub_root": "Children will become root tags",
 	"admin_tag_delete_subtree": "Delete entire subtree",
 	"admin_tag_delete_subtree_warn": "Also deletes {count} child tags",
-	"admin_tag_delete_confirm_heading": "Type «{name}» to confirm:"
+	"admin_tag_delete_confirm_heading": "Type «{name}» to confirm:",
+	"filter_operator_and": "AND",
+	"filter_operator_or": "OR",
+	"filter_operator_and_label": "All selected tags must match (AND)",
+	"filter_operator_or_label": "At least one tag must match (OR)"
 }

frontend/messages/es.json

@@ -604,5 +604,9 @@
 	"admin_tag_delete_only_this_sub_root": "Las subordinadas se convertirán en etiquetas raíz",
 	"admin_tag_delete_subtree": "Eliminar todo el subárbol",
 	"admin_tag_delete_subtree_warn": "También elimina {count} etiquetas subordinadas",
-	"admin_tag_delete_confirm_heading": "Escribe «{name}» para confirmar:"
+	"admin_tag_delete_confirm_heading": "Escribe «{name}» para confirmar:",
+	"filter_operator_and": "Y",
+	"filter_operator_or": "O",
+	"filter_operator_and_label": "Todas las etiquetas seleccionadas deben coincidir (Y)",
+	"filter_operator_or_label": "Al menos una etiqueta debe coincidir (O)"
 }

frontend/src/lib/components/TagInput.svelte

@@ -119,7 +119,7 @@ function handleKeydown(e: KeyboardEvent) {
 		class="flex min-h-[42px] flex-wrap gap-2 rounded border border-line bg-surface p-2 focus-within:border-ink focus-within:ring-1 focus-within:ring-ink"
 	>
 		<!-- Render Selected Tags -->
-		{#each tags as tag, i (i)}
+		{#each tags as tag, i (tag.id ?? tag.name)}
 			<span class="flex items-center gap-1 rounded bg-muted px-2 py-1 text-sm font-medium text-ink">
 				{#if tag.color}
 					<span
@@ -169,7 +169,7 @@ function handleKeydown(e: KeyboardEvent) {
 				<ul
 					class="absolute top-full left-0 z-50 mt-1 max-h-48 w-full overflow-y-auto rounded border border-line bg-surface shadow-lg"
 				>
-					{#each orderedSuggestions as suggestion, i (i)}
+					{#each orderedSuggestions as suggestion, i (suggestion.id ?? suggestion.name)}
 						<li
 							role="option"
 							aria-selected={i === activeIndex}

frontend/src/routes/SearchFilterBar.svelte

@@ -161,19 +161,27 @@ $effect(() => {
 					<div data-testid="and-or-toggle" class="mt-2 flex items-center gap-1">
 						<button
 							type="button"
+							data-testid="operator-and"
+							aria-label={m.filter_operator_and_label()}
+							aria-pressed={tagOperator === 'AND'}
 							class="rounded px-2 py-0.5 text-xs font-bold tracking-widest uppercase transition-colors {tagOperator === 'AND' ? 'bg-primary text-primary-fg' : 'bg-muted text-ink-2 hover:bg-line'}"
 							onclick={() => {
 								tagOperator = 'AND';
 								(onSearchImmediate ?? onSearch)();
-							}}>AND</button
+							}}
+							>{m.filter_operator_and()}</button
 						>
 						<button
 							type="button"
+							data-testid="operator-or"
+							aria-label={m.filter_operator_or_label()}
+							aria-pressed={tagOperator === 'OR'}
 							class="rounded px-2 py-0.5 text-xs font-bold tracking-widest uppercase transition-colors {tagOperator === 'OR' ? 'bg-primary text-primary-fg' : 'bg-muted text-ink-2 hover:bg-line'}"
 							onclick={() => {
 								tagOperator = 'OR';
 								(onSearchImmediate ?? onSearch)();
-							}}>OR</button
+							}}
+							>{m.filter_operator_or()}</button
 						>
 					</div>
 				{/if}

frontend/src/routes/SearchFilterBar.svelte.spec.ts

@@ -61,7 +61,7 @@ describe('SearchFilterBar – AND/OR tag operator toggle', () => {
 			tagNames: [{ name: 'Tag1' }]
 		});
 		await openAdvanced();
-		await expect.element(page.getByRole('button', { name: 'AND' })).not.toBeInTheDocument();
+		await expect.element(page.getByTestId('operator-and')).not.toBeInTheDocument();
 		vi.unstubAllGlobals();
 	});
 
@@ -79,8 +79,8 @@ describe('SearchFilterBar – AND/OR tag operator toggle', () => {
 		await openAdvanced();
 		const toggle = page.getByTestId('and-or-toggle');
 		await expect.element(toggle).toBeInTheDocument();
-		await expect.element(toggle.getByRole('button', { name: 'AND' })).toBeInTheDocument();
+		await expect.element(toggle.getByTestId('operator-and')).toBeInTheDocument();
-		await expect.element(toggle.getByRole('button', { name: 'OR' })).toBeInTheDocument();
+		await expect.element(toggle.getByTestId('operator-or')).toBeInTheDocument();
 		vi.unstubAllGlobals();
 	});
 
@@ -99,7 +99,7 @@ describe('SearchFilterBar – AND/OR tag operator toggle', () => {
 		});
 		await openAdvanced();
 		const toggle = page.getByTestId('and-or-toggle');
-		await toggle.getByRole('button', { name: 'OR' }).click();
+		await toggle.getByTestId('operator-or').click();
 		await expect.poll(() => onSearch.mock.calls.length).toBeGreaterThan(0);
 		vi.unstubAllGlobals();
 	});
@@ -121,7 +121,7 @@ describe('SearchFilterBar – AND/OR tag operator toggle', () => {
 		});
 		await openAdvanced();
 		const toggle = page.getByTestId('and-or-toggle');
-		await toggle.getByRole('button', { name: 'OR' }).click();
+		await toggle.getByTestId('operator-or').click();
 		await expect.poll(() => onSearchImmediate.mock.calls.length).toBeGreaterThan(0);
 		expect(onSearch).not.toHaveBeenCalled();
 		vi.unstubAllGlobals();

frontend/src/routes/admin/tags/[id]/TagMergeZone.svelte

@@ -50,8 +50,8 @@ const targetTag = $derived(allTags.find((t) => t.id === targetId));
 	</h3>
 	<p class="mb-4 text-xs text-ink-3">{m.admin_tag_merge_description()}</p>
 
-	<!-- Step indicator -->
+	<!-- Step indicator (aria-live announces step changes to screen reader users) -->
-	<p class="mb-3 text-xs font-medium text-ink-3">
+	<p class="mb-3 text-xs font-medium text-ink-3" aria-live="polite" role="status">
 		{step === 1 ? m.admin_tag_merge_step1() : m.admin_tag_merge_step2()}
 	</p>