fix(tasks): keep emoji / surrogate pairs intact during terminal output truncation (#101600)

* fix(tasks): keep emoji / surrogate pairs intact during terminal output truncation

.slice() counts UTF-16 code units; use Array.from() to count full
code points instead, preventing lone surrogates in task list output.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* fix(tasks): preserve terminal column width

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Co-authored-by: Peter Steinberger <steipete@gmail.com>

src/commands/tasks.test.ts

@@ -24,6 +24,7 @@ import type { OpenClawTestState } from "../test-utils/openclaw-test-state.js";
 import {
   tasksAuditCommand,
   tasksCancelCommand,
+  tasksListCommand,
   tasksMaintenanceCommand,
   tasksShowCommand,
 } from "./tasks.js";
@@ -601,6 +602,30 @@ describe("tasks commands", () => {
     });
   });
 
+  it("keeps task list summaries within their UTF-16 column limit", async () => {
+    await withTaskCommandStateDir(async () => {
+      createTaskRecord({
+        runtime: "cli",
+        ownerKey: "agent:main:main",
+        scopeKind: "session",
+        runId: "task-utf16-summary",
+        status: "succeeded",
+        task: "Inspect task summary",
+        terminalSummary: `${"y".repeat(78)}🚀xx`,
+      });
+      const runtime = createRuntime();
+
+      await tasksListCommand({}, runtime);
+
+      const output = vi
+        .mocked(runtime.log)
+        .mock.calls.map(([line]) => String(line))
+        .join("\n");
+      expect(output).toContain(`${"y".repeat(78)}…`);
+      expect(output).not.toContain("🚀");
+    });
+  });
+
   it("explains retained lost task cleanup timing in maintenance text output", async () => {
     await withTaskCommandStateDir(async () => {
       const cleanupAfter = Date.now() + 60_000;

src/commands/tasks.ts

@@ -3,6 +3,7 @@
 
 import { timestampMsToIsoString } from "@openclaw/normalization-core/number-coercion";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
+import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { isRich, theme } from "../../packages/terminal-core/src/theme.js";
 import { formatCliCommand } from "../cli/command-format.js";
 import { formatLookupMiss } from "../cli/error-format.js";
@@ -205,10 +206,7 @@ function truncate(value: string, maxChars: number) {
   if (value.length <= maxChars) {
     return value;
   }
-  if (maxChars <= 1) {
-    return value.slice(0, maxChars);
-  }
-  return `${value.slice(0, maxChars - 1)}…`;
+  return maxChars <= 0 ? "" : `${truncateUtf16Safe(value, maxChars - 1)}…`;
 }
 
 function shortToken(value: string | undefined, maxChars = ID_PAD): string {