fix: preserve nested rest patterns in {#each} destructuring context

.changeset/nested-each-rest.md

@@ -0,0 +1,5 @@
+---
+"prettier-plugin-svelte": patch
+---
+
+fix: preserve nested rest patterns in `{#each}` destructuring

src/print/index.ts

@@ -1454,7 +1454,8 @@ function _expandNode(node: any, original: string, parent?: any): string {
             }
         }
         case 'RestElement':
-            return ' ...' + node.argument.name;
+            // argument may be a nested Array/ObjectPattern, not only an Identifier
+            return ' ...' + _expandNode(node.argument, original).slice(1);
     }
 
     console.error(JSON.stringify(node, null, 4));

test/printer/samples/each-block-destructured-nested-rest.html

@@ -0,0 +1,7 @@
+{#each array as [first, second, ...[third, ...{ length }]]}
+    <p>{first} {second} {third} {length}</p>
+{/each}
+
+{#each items as [head, ...{ length }]}
+    <p>{head} {length}</p>
+{/each}