feat: add background bash sessions

src/agents/bash-process-registry.test.ts

@@ -0,0 +1,76 @@
+import { beforeEach, describe, expect, it } from "vitest";
+import {
+  addSession,
+  appendOutput,
+  listFinishedSessions,
+  markBackgrounded,
+  markExited,
+  resetProcessRegistryForTests,
+} from "./bash-process-registry.js";
+
+type DummyChild = {
+  pid?: number;
+};
+
+describe("bash process registry", () => {
+  beforeEach(() => {
+    resetProcessRegistryForTests();
+  });
+
+  it("captures output and truncates", () => {
+    const session = {
+      id: "sess",
+      command: "echo test",
+      child: { pid: 123 } as DummyChild,
+      startedAt: Date.now(),
+      cwd: "/tmp",
+      maxOutputChars: 10,
+      totalOutputChars: 0,
+      pendingStdout: [],
+      pendingStderr: [],
+      aggregated: "",
+      tail: "",
+      exited: false,
+      exitCode: undefined,
+      exitSignal: undefined,
+      truncated: false,
+      backgrounded: false,
+    };
+
+    addSession(session as any);
+    appendOutput(session as any, "stdout", "0123456789");
+    appendOutput(session as any, "stdout", "abcdef");
+
+    expect(session.aggregated).toBe("6789abcdef");
+    expect(session.truncated).toBe(true);
+  });
+
+  it("only persists finished sessions when backgrounded", () => {
+    const session = {
+      id: "sess",
+      command: "echo test",
+      child: { pid: 123 } as DummyChild,
+      startedAt: Date.now(),
+      cwd: "/tmp",
+      maxOutputChars: 100,
+      totalOutputChars: 0,
+      pendingStdout: [],
+      pendingStderr: [],
+      aggregated: "",
+      tail: "",
+      exited: false,
+      exitCode: undefined,
+      exitSignal: undefined,
+      truncated: false,
+      backgrounded: false,
+    };
+
+    addSession(session as any);
+    markExited(session as any, 0, null, "completed");
+    expect(listFinishedSessions()).toHaveLength(0);
+
+    markBackgrounded(session as any);
+    markExited(session as any, 0, null, "completed");
+    expect(listFinishedSessions()).toHaveLength(1);
+  });
+});