fix(matrix): sanitize internal tool-trace lines from outbound text (#97372)

Wrap the matrix outbound sanitizeText hook with sanitizeAssistantVisibleText so assistant internal tool-trace scaffolding is stripped before delivery, matching the sibling channel fixes under #90684 (Telegram #95774, Google Chat #95084, IRC #97214).

extensions/matrix/src/channel.ts

@@ -32,7 +32,10 @@ import {
   normalizeLowercaseStringOrEmpty,
   normalizeOptionalString,
 } from "openclaw/plugin-sdk/string-coerce-runtime";
-import { chunkTextForOutbound } from "openclaw/plugin-sdk/text-chunking";
+import {
+  chunkTextForOutbound,
+  sanitizeAssistantVisibleText,
+} from "openclaw/plugin-sdk/text-chunking";
 import { matrixMessageActions } from "./actions.js";
 import { matrixApprovalCapability } from "./approval-native.js";
 import { createMatrixPairingText, createMatrixProbeAccount } from "./channel-account-paths.js";
@@ -336,6 +339,7 @@ const matrixChannelOutbound: ChannelOutboundAdapter = {
   chunker: chunkTextForOutbound,
   chunkerMode: "markdown",
   textChunkLimit: 4000,
+  sanitizeText: ({ text }) => sanitizeAssistantVisibleText(text),
   deliveryCapabilities: {
     durableFinal: {
       text: true,

extensions/matrix/src/outbound-tool-trace-sanitize.test.ts

@@ -0,0 +1,20 @@
+// Matrix outbound must strip assistant internal tool-trace scaffolding, matching
+// the sibling channel fixes tracked under #90684 (Telegram #95774 / Google Chat
+// #95084 / IRC #97214). The hook runs before the markdown->HTML render, so a
+// single sanitize cleans both the plain body and the formatted_body.
+import { describe, expect, it } from "vitest";
+import { matrixPlugin } from "./channel.js";
+
+describe("matrix outbound sanitizeText", () => {
+  it("strips internal tool-trace banners before outbound delivery", () => {
+    const text = "Done.\n⚠️ 🛠️ `search repos (agent)` failed";
+
+    expect(matrixPlugin.outbound?.sanitizeText?.({ text, payload: { text } })).toBe("Done.");
+  });
+
+  it("preserves ordinary assistant prose while sanitizing", () => {
+    const text = "The pipeline has 3 open deals.";
+
+    expect(matrixPlugin.outbound?.sanitizeText?.({ text, payload: { text } })).toBe(text);
+  });
+});