Fix undefined on multi-file apply_diff output (#4608)

feat: enhance file handling in `apply_diff` case to support legacy and multi-file formats

src/core/assistant-message/presentAssistantMessage.ts

@@ -161,7 +161,24 @@ export async function presentAssistantMessage(cline: Task) {
 					case "write_to_file":
 						return `[${block.name} for '${block.params.path}']`
 					case "apply_diff":
-						return `[${block.name} for '${block.params.path}']`
+						// Handle both legacy format and new multi-file format
+						if (block.params.path) {
+							return `[${block.name} for '${block.params.path}']`
+						} else if (block.params.args) {
+							// Try to extract first file path from args for display
+							const match = block.params.args.match(/<file>.*?<path>([^<]+)<\/path>/s)
+							if (match) {
+								const firstPath = match[1]
+								// Check if there are multiple files
+								const fileCount = (block.params.args.match(/<file>/g) || []).length
+								if (fileCount > 1) {
+									return `[${block.name} for '${firstPath}' and ${fileCount - 1} more file${fileCount > 2 ? "s" : ""}]`
+								} else {
+									return `[${block.name} for '${firstPath}']`
+								}
+							}
+						}
+						return `[${block.name}]`
 					case "search_files":
 						return `[${block.name} for '${block.params.regex}'${
 							block.params.file_pattern ? ` in '${block.params.file_pattern}'` : ""