Bootstrap rein-openweights: minimal agentic loop over OpenRouter (REIN-OW-WP-0001)

Implements T01-T04:
- tools.py: green-commit-only-equivalent tool surface (read/write/edit/
  glob/grep + git status/diff/log/add+commit), path-traversal guarded.
- openrouter_client.py: own minimal chat-completions client — llm-connect's
  OpenRouterAdapter takes a single prompt string and never surfaces
  tool_calls, so it can't drive a multi-turn tool-calling loop without a
  breaking change to its frozen Core ABC. llm-connect stays an optional
  dependency (pyproject.toml), not load-bearing.
- loop.py: plan -> tool call -> observe -> repeat, budget- and
  turn-bounded, tool errors reported back to the model instead of
  crashing the loop.
- credentials.py: own OpenBao AppRole/ambient-token acquisition, per
  glas-harness ADR-002 (Option B) — glas-harness does not broker this.
- runner.py/hub.py: commit-verified success criterion + State Hub
  progress/token reporting, mirroring rein-aharness's model.

26 tests, all mocked at the httpx/subprocess boundary — no real
OpenRouter or OpenBao calls made. T05 (Forgejo repo creation) stays
open, deferred to the operator.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

tests/test_openrouter_client.py

@@ -0,0 +1,43 @@
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from rein_openweights.openrouter_client import OpenRouterClient, OpenRouterError
+
+
+def test_chat_sends_bearer_auth_and_model():
+    client = OpenRouterClient(api_key="sk-test", model="meta-llama/llama-3.1-70b-instruct")
+    fake_response = MagicMock(status_code=200)
+    fake_response.json.return_value = {"choices": [{"message": {"content": "hi"}}]}
+
+    with patch("rein_openweights.openrouter_client.httpx.post", return_value=fake_response) as post:
+        data = client.chat([{"role": "user", "content": "hello"}])
+
+    assert data["choices"][0]["message"]["content"] == "hi"
+    _, kwargs = post.call_args
+    assert kwargs["headers"]["Authorization"] == "Bearer sk-test"
+    assert kwargs["json"]["model"] == "meta-llama/llama-3.1-70b-instruct"
+    assert "tools" not in kwargs["json"]
+
+
+def test_chat_includes_tools_when_provided():
+    client = OpenRouterClient(api_key="sk-test", model="m")
+    fake_response = MagicMock(status_code=200)
+    fake_response.json.return_value = {"choices": [{"message": {}}]}
+    tools = [{"type": "function", "function": {"name": "read_file"}}]
+
+    with patch("rein_openweights.openrouter_client.httpx.post", return_value=fake_response) as post:
+        client.chat([{"role": "user", "content": "x"}], tools=tools)
+
+    _, kwargs = post.call_args
+    assert kwargs["json"]["tools"] == tools
+    assert kwargs["json"]["tool_choice"] == "auto"
+
+
+def test_chat_raises_on_http_error():
+    client = OpenRouterClient(api_key="sk-test", model="m")
+    fake_response = MagicMock(status_code=401, text="unauthorized")
+
+    with patch("rein_openweights.openrouter_client.httpx.post", return_value=fake_response):
+        with pytest.raises(OpenRouterError, match="401"):
+            client.chat([{"role": "user", "content": "x"}])