fix: suppress terminal query response leaks

packages/server/src/terminal/terminal.test.ts

@@ -978,6 +978,23 @@ describe("subscribe", () => {
 
     expect(messages.length).toBe(0);
   });
+
+  it("does not answer terminal identity queries from the headless snapshot parser", async () => {
+    const session = trackSession(
+      await createTerminal({
+        cwd: "/tmp",
+        shell: "/bin/sh",
+        env: { PS1: "$ " },
+      }),
+    );
+
+    await waitForLines(session, ["$"]);
+
+    session.send({ type: "input", data: "printf '\\033[c'; echo after-da\r" });
+    await waitForState(session, (state) => getLines(state).join("\n").includes("after-da"));
+
+    expect(getLines(session.getState()).join("\n")).not.toContain("62;4;22c");
+  });
 });
 
 describe("stream snapshots", () => {

packages/server/src/terminal/terminal.ts

@@ -657,15 +657,6 @@ export async function createTerminal(options: CreateTerminalOptions): Promise<Te
   }
   emitTitleChange(initialTitle);
 
-  // Respond to DA1 queries (CSI c or CSI 0 c) — apps like nvim query terminal capabilities
-  terminal.parser.registerCsiHandler({ final: "c" }, (params) => {
-    if (params.length === 0 || (params.length === 1 && params[0] === 0)) {
-      ptyProcess.write("\x1b[?62;4;22c");
-      return true;
-    }
-    return false;
-  });
-
   let disposeTitleChangeSubscription: { dispose(): void } | null = null;
   if (!lockedTitle) {
     disposeTitleChangeSubscription = terminal.onTitleChange((nextTitle) => {