test(matrix,discord,sandbox): expand breakage regression coverage

src/agents/sandbox/fs-bridge.test.ts

@@ -91,6 +91,22 @@ describe("sandbox fs bridge shell compatibility", () => {
     expect(canonicalScript).toBeDefined();
     // "; " joining can create "do; cmd", which is invalid in POSIX sh.
     expect(canonicalScript).not.toMatch(/\bdo;/);
+    // Keep command on the next line after "do" for POSIX-sh safety.
+    expect(canonicalScript).toMatch(/\bdo\n\s*parent=/);
+  });
+
+  it("reads inbound media-style filenames with triple-dash ids", async () => {
+    const bridge = createSandboxFsBridge({ sandbox: createSandbox() });
+    const inboundPath = "media/inbound/file_1095---f00a04a2-99a0-4d98-99b0-dfe61c5a4198.ogg";
+
+    await bridge.readFile({ filePath: inboundPath });
+
+    const readCall = mockedExecDockerRaw.mock.calls.find(([args]) =>
+      String(args[5] ?? "").includes('cat -- "$1"'),
+    );
+    expect(readCall).toBeDefined();
+    const readPath = String(readCall?.[0].at(-1) ?? "");
+    expect(readPath).toContain("file_1095---");
   });
 
   it("resolves bind-mounted absolute container paths for reads", async () => {

src/discord/monitor/message-handler.process.test.ts

@@ -444,6 +444,24 @@ describe("processDiscordMessage draft streaming", () => {
     expect(deliverDiscordReply).not.toHaveBeenCalled();
   });
 
+  it("suppresses reasoning-tagged final payload delivery to Discord", async () => {
+    dispatchInboundMessage.mockImplementationOnce(async (params?: DispatchInboundParams) => {
+      await params?.dispatcher.sendFinalReply({
+        text: "Reasoning:\nthis should stay internal",
+        isReasoning: true,
+      } as never);
+      return { queuedFinal: true, counts: { final: 1, tool: 0, block: 0 } };
+    });
+
+    const ctx = await createBaseContext({ discordConfig: { streamMode: "off" } });
+
+    // oxlint-disable-next-line typescript/no-explicit-any
+    await processDiscordMessage(ctx as any);
+
+    expect(deliverDiscordReply).not.toHaveBeenCalled();
+    expect(editMessageDiscord).not.toHaveBeenCalled();
+  });
+
   it("delivers non-reasoning block payloads to Discord", async () => {
     dispatchInboundMessage.mockImplementationOnce(async (params?: DispatchInboundParams) => {
       await params?.dispatcher.sendBlockReply({ text: "hello from block stream" });