fix(cli): label OpenRouter prompts and shortlist mainstream models

Label each OpenRouter model prompt by mode (quick/deep) like the other
providers, so the two consecutive selections are distinguishable. Populate the
dropdown with the newest models from mainstream chat providers rather than the
universal-newest (which surfaced niche/experimental releases); Custom ID still
reaches anything. Cancelled required prompts now exit cleanly instead of
crashing, and the output-language prompt falls back to English.

tests/test_openrouter_model_select.py

@@ -0,0 +1,122 @@
+"""OpenRouter model selection: prompts are labeled by mode (#1000); required
+prompts exit cleanly on cancel; the output-language prompt defaults to English
+on cancel; and the OpenRouter list is newest-first."""
+
+from unittest import mock
+
+import pytest
+
+from cli import utils
+
+
+def _asks(value):
+    return mock.Mock(ask=mock.Mock(return_value=value))
+
+
+@pytest.mark.unit
+class TestOpenRouterPromptLabel:
+    @pytest.mark.parametrize("mode,label", [("quick", "Quick-Thinking"), ("deep", "Deep-Thinking")])
+    def test_prompt_states_the_mode(self, mode, label):
+        captured = {}
+
+        def fake_select(message, **kwargs):
+            captured["message"] = message
+            return _asks("openrouter/some-model")
+
+        with mock.patch.object(utils, "_fetch_openrouter_models",
+                               return_value=[("Some Model", "openrouter/some-model")]), \
+             mock.patch.object(utils.questionary, "select", side_effect=fake_select):
+            out = utils.select_openrouter_model(mode)
+
+        assert label in captured["message"]
+        assert out == "openrouter/some-model"
+
+
+@pytest.mark.unit
+class TestOpenRouterLatestFirst:
+    def test_models_sorted_newest_first(self):
+        payload = {"data": [
+            {"id": "old/model", "name": "Old", "created": 1000},
+            {"id": "new/model", "name": "New", "created": 3000},
+            {"id": "mid/model", "name": "Mid", "created": 2000},
+        ]}
+        resp = mock.Mock()
+        resp.json.return_value = payload
+        resp.raise_for_status = mock.Mock()
+        with mock.patch("requests.get", return_value=resp):
+            out = utils._fetch_openrouter_models()
+        assert [mid for _, mid in out] == ["new/model", "mid/model", "old/model"]
+
+
+@pytest.mark.unit
+class TestMainstreamFilter:
+    def test_dropdown_prefers_mainstream_over_niche(self):
+        # _fetch returns newest-first; the shortlist should drop niche namespaces.
+        models = [
+            ("Fusion", "openrouter/fusion"),
+            ("Niche", "nex-agi/nex-n2-pro:free"),
+            ("Claude", "anthropic/claude-x"),
+            ("GPT", "openai/gpt-x"),
+        ]
+        captured = {}
+
+        def fake_select(message, **kwargs):
+            captured["values"] = [c.value for c in kwargs["choices"]]
+            return _asks("anthropic/claude-x")
+
+        with mock.patch.object(utils, "_fetch_openrouter_models", return_value=models), \
+             mock.patch.object(utils.questionary, "select", side_effect=fake_select):
+            utils.select_openrouter_model("quick")
+
+        assert "anthropic/claude-x" in captured["values"]
+        assert "openai/gpt-x" in captured["values"]
+        assert "openrouter/fusion" not in captured["values"]
+        assert "nex-agi/nex-n2-pro:free" not in captured["values"]
+        assert "custom" in captured["values"]  # escape hatch preserved
+
+    def test_falls_back_to_all_when_no_mainstream(self):
+        models = [("Niche", "nex-agi/x"), ("Other", "thedrummer/y")]
+        captured = {}
+
+        def fake_select(message, **kwargs):
+            captured["values"] = [c.value for c in kwargs["choices"]]
+            return _asks("nex-agi/x")
+
+        with mock.patch.object(utils, "_fetch_openrouter_models", return_value=models), \
+             mock.patch.object(utils.questionary, "select", side_effect=fake_select):
+            utils.select_openrouter_model("deep")
+
+        assert "nex-agi/x" in captured["values"]  # fallback keeps the list usable
+
+
+@pytest.mark.unit
+class TestCancelExitsCleanly:
+    def test_dropdown_cancel_exits(self):
+        with mock.patch.object(utils, "_fetch_openrouter_models", return_value=[]), \
+             mock.patch.object(utils.questionary, "select", return_value=_asks(None)), \
+             pytest.raises(SystemExit):
+            utils.select_openrouter_model("quick")
+
+    def test_custom_id_cancel_exits(self):
+        with mock.patch.object(utils, "_fetch_openrouter_models", return_value=[]), \
+             mock.patch.object(utils.questionary, "select", return_value=_asks("custom")), \
+             mock.patch.object(utils.questionary, "text", return_value=_asks(None)), \
+             pytest.raises(SystemExit):
+            utils.select_openrouter_model("deep")
+
+    def test_prompt_custom_model_id_cancel_exits(self):
+        with mock.patch.object(utils.questionary, "text", return_value=_asks(None)), \
+             pytest.raises(SystemExit):
+            utils._prompt_custom_model_id()
+
+
+@pytest.mark.unit
+class TestLanguageDefaultsToEnglish:
+    def test_select_cancel_defaults_english(self):
+        with mock.patch.object(utils.questionary, "select", return_value=_asks(None)):
+            assert utils.ask_output_language() == "English"
+
+    def test_custom_language_cancel_defaults_english(self):
+        with mock.patch.object(utils.questionary, "select", return_value=_asks("custom")), \
+             mock.patch.object(utils.questionary, "text", return_value=_asks(None)):
+            assert utils.ask_output_language() == "English"