fix(journey-item-row): add journey_remove_item_aria key and fix remove button label

The remove button was using the confirmation-question text as its
aria-label. Added a new dedicated journey_remove_item_aria key
in all three locales so the button has a clear accessible name
before the confirmation dialog opens.

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

frontend/src/lib/geschichte/JourneyItemRow.svelte

@@ -144,7 +144,7 @@ function handleRemoveClick() {
 				<button
 					type="button"
 					onclick={handleRemoveClick}
-					aria-label={m.journey_remove_confirm()}
+					aria-label={m.journey_remove_item_aria()}
 					class="-m-1 rounded p-3 text-ink-3 hover:text-danger focus:outline-none focus-visible:ring-2 focus-visible:ring-focus-ring"
 				>
 					<svg