fix(editor): Restrict [empty] in parameter input hint to zero-length string (#6003)

* 🚧 Quick test

* ⚡ Adjust to new requirements

* ⚡ Account for 2x double quotes

* 🔥 Remove excess single quote

* ⏪ Revert per new requirements

* ⏪ Undo more changes to minimize diff

* ⏪ New requirement changes

* 🐛 Prevent excess whitespace from HTML formatting

* 🚚 Rename computed property

* 🧪 Set up e2e tests for parameter input hint

* 🚧 Experiments with unit tests

Pinia stores setup process WIP.

* 🔥 Remove e2e test

* ⏪ Restore `test` command

* 🔥 Remove unit test stub

* 🔥 Remove logging

* 🔥 Remove test ID

* 🧪 Fix e2e test

* 🧪 Tighten text check

packages/editor-ui/src/components/ParameterInputHint.vue

@@ -1,11 +1,6 @@
 <template>
 	<n8n-text size="small" color="text-base" tag="div" v-if="hint">
-		<div
-			v-if="!renderHTML"
-			:class="{ [$style.singleline]: singleLine, [$style.highlight]: highlight }"
-		>
-			{{ hint }}
-		</div>
+		<div v-if="!renderHTML" :class="classes">{{ hint }}</div>
 		<div
 			v-else
 			ref="hint"
@@ -39,6 +34,15 @@ export default defineComponent({
 	methods: {
 		sanitizeHtml,
 	},
+	computed: {
+		classes() {
+			return {
+				[this.$style.singleline]: this.singleLine,
+				[this.$style.highlight]: this.highlight,
+				[this.$style['preserve-whitespace']]: true,
+			};
+		},
+	},
 	mounted() {
 		if (this.$refs.hint) {
 			(this.$refs.hint as Element).querySelectorAll('a').forEach((a) => (a.target = '_blank'));
@@ -56,4 +60,7 @@ export default defineComponent({
 .highlight {
 	color: var(--color-secondary);
 }
+.preserve-whitespace {
+	white-space: pre;
+}
 </style>