Improve navigation footer bar hints

frontend/src/components/widgets/labels/UserInputLabel.svelte

@@ -225,7 +225,7 @@
 			}
 		}
 
-		.hint-text {
+		.hint-text:not(:empty) {
 			margin-left: 4px;
 		}
 

frontend/src/components/window/status-bar/StatusBar.svelte

@@ -35,6 +35,9 @@
 				{#if hint.plus}
 					<LayoutRow class="plus">+</LayoutRow>
 				{/if}
+				{#if hint.slash}
+					<LayoutRow class="slash">/</LayoutRow>
+				{/if}
 				<UserInputLabel mouseMotion={hint.mouse} keysWithLabelsGroups={inputKeysForPlatform(hint)}>{hint.label}</UserInputLabel>
 			{/each}
 		{/each}
@@ -57,7 +60,8 @@
 				margin: 0;
 			}
 
-			.plus {
+			.plus,
+			.slash {
 				flex: 0 0 auto;
 				align-items: center;
 				font-weight: 700;

frontend/src/wasm-communication/messages.ts

@@ -172,6 +172,8 @@ export class HintInfo {
 	readonly label!: string;
 
 	readonly plus!: boolean;
+
+	readonly slash!: boolean;
 }
 
 // Rust enum `Key`