feat(cli): add interactive follow-up loop with slash commands

tests/test_cli.py

@@ -139,3 +139,71 @@ def test_collect_success_prints_summary(monkeypatch) -> None:  # type: ignore[no
     assert "Collection complete" in result.stdout
     assert "kernel: ok" in result.stdout
     assert "journal: ok (truncated)" in result.stdout
+
+
+def test_interactive_collect_then_quit(monkeypatch) -> None:  # type: ignore[no-untyped-def]
+    _mock_session(monkeypatch)
+
+    async def fake_collect_from_plan(_session, _plan) -> CollectionReport:  # type: ignore[no-untyped-def]
+        return CollectionReport(
+            host="ssh.archflux.net",
+            items=[
+                CollectedItem(
+                    name="kernel",
+                    result=SSHCommandResult(
+                        command="uname -a",
+                        exit_code=0,
+                        stdout="Linux test",
+                        stderr="",
+                    ),
+                ),
+            ],
+        )
+
+    commands = iter(["/collect", "/quit"])
+
+    monkeypatch.setattr("tai.cli.collect_from_plan", fake_collect_from_plan)
+    monkeypatch.setattr("builtins.input", lambda _prompt: next(commands))
+
+    runner = CliRunner()
+    result = runner.invoke(
+        app,
+        [
+            "apache failed",
+            "--host",
+            "ssh.archflux.net",
+            "--port",
+            "5566",
+            "--no-probe",
+            "--interactive",
+        ],
+    )
+
+    assert result.exit_code == 0
+    assert "Interactive mode" in result.stdout
+    assert "Collection complete" in result.stdout
+    assert "Bye." in result.stdout
+
+
+def test_interactive_unknown_command_prints_hint(monkeypatch) -> None:  # type: ignore[no-untyped-def]
+    _mock_session(monkeypatch)
+
+    commands = iter(["/wat", "/quit"])
+    monkeypatch.setattr("builtins.input", lambda _prompt: next(commands))
+
+    runner = CliRunner()
+    result = runner.invoke(
+        app,
+        [
+            "apache failed",
+            "--host",
+            "ssh.archflux.net",
+            "--port",
+            "5566",
+            "--no-probe",
+            "--interactive",
+        ],
+    )
+
+    assert result.exit_code == 0
+    assert "Unknown command" in result.stdout