test: add Cortex test suite (77 tests, no LLM calls)

Tests cover:
  - Smoke: /health, /auth/status, /distill/status (test_health.py)
  - Persona validation: path traversal, bad names, list_personas (test_persona.py)
  - Chat API: persona routing, session persistence, error handling (test_api_chat.py)
  - Files API: ALLOWED set enforcement, read/write, missing files (test_api_files.py)
  - Webhooks: NC Talk HMAC accept/reject, Google Chat JWT (test_webhooks.py)
  - Tools: scratch read/write/append/clear, tasks CRUD, cron parser + tools (test_tools.py)
  - Security: path traversal, replay attack, known gaps documented (test_security.py)

All LLM calls mocked — suite runs in ~1.4s.
Run: cd cortex && .venv/bin/pytest

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cortex/tests/test_webhooks.py

@@ -0,0 +1,164 @@
+"""
+Webhook auth tests — NC Talk HMAC, Google Chat JWT.
+
+These tests verify that auth is enforced, not that full LLM responses work.
+"""
+import hashlib
+import hmac
+import json
+import pytest
+from unittest.mock import AsyncMock, patch
+
+
+# ---------------------------------------------------------------------------
+# Nextcloud Talk
+# ---------------------------------------------------------------------------
+
+_NC_SECRET = "test-bot-secret-12345"
+
+_VALID_NC_PAYLOAD = {
+    "type": "Create",
+    "actor": {"type": "users", "id": "testuser", "name": "Test User"},
+    "object": {
+        "type": "Note",
+        "content": json.dumps({"message": "Hello Inara"}),
+    },
+    "target": {"id": "abc123token"},
+}
+
+
+def _nc_headers(body: bytes, secret: str) -> dict:
+    random_str = "abc123"
+    sig = hmac.new(
+        secret.encode(),
+        (random_str + body.decode("utf-8")).encode(),
+        hashlib.sha256,
+    ).hexdigest()
+    return {
+        "X-Nextcloud-Talk-Random": random_str,
+        "X-Nextcloud-Talk-Signature": sig,
+    }
+
+
+@pytest.mark.anyio
+async def test_nct_valid_signature(client, mock_llm):
+    body = json.dumps(_VALID_NC_PAYLOAD).encode()
+    with patch("config.settings.nextcloud_talk_bot_secret", _NC_SECRET):
+        with patch("routers.nextcloud_talk._send_reply", new_callable=AsyncMock):
+            headers = _nc_headers(body, _NC_SECRET)
+            r = await client.post(
+                "/inara-nextcloud-talk-webhook",
+                content=body,
+                headers={**headers, "Content-Type": "application/json"},
+            )
+    assert r.status_code == 200
+
+
+@pytest.mark.anyio
+async def test_nct_wrong_signature(client):
+    body = json.dumps(_VALID_NC_PAYLOAD).encode()
+    with patch("config.settings.nextcloud_talk_bot_secret", _NC_SECRET):
+        r = await client.post(
+            "/inara-nextcloud-talk-webhook",
+            content=body,
+            headers={
+                "Content-Type": "application/json",
+                "X-Nextcloud-Talk-Random": "abc123",
+                "X-Nextcloud-Talk-Signature": "badsignature",
+            },
+        )
+    assert r.status_code == 401
+
+
+@pytest.mark.anyio
+async def test_nct_missing_signature(client):
+    body = json.dumps(_VALID_NC_PAYLOAD).encode()
+    with patch("config.settings.nextcloud_talk_bot_secret", _NC_SECRET):
+        r = await client.post(
+            "/inara-nextcloud-talk-webhook",
+            content=body,
+            headers={"Content-Type": "application/json"},
+        )
+    assert r.status_code == 401
+
+
+@pytest.mark.anyio
+async def test_nct_no_secret_configured(client):
+    """Service should return 500 if secret is not set, not process the message."""
+    body = json.dumps(_VALID_NC_PAYLOAD).encode()
+    with patch("config.settings.nextcloud_talk_bot_secret", ""):
+        r = await client.post(
+            "/inara-nextcloud-talk-webhook",
+            content=body,
+            headers={"Content-Type": "application/json"},
+        )
+    assert r.status_code == 500
+
+
+@pytest.mark.anyio
+async def test_nct_bot_message_ignored(client):
+    """Messages from other bots should be silently ignored (not processed)."""
+    payload = {**_VALID_NC_PAYLOAD, "actor": {"type": "bots", "id": "otherbot", "name": "Bot"}}
+    body = json.dumps(payload).encode()
+    with patch("config.settings.nextcloud_talk_bot_secret", _NC_SECRET):
+        headers = _nc_headers(body, _NC_SECRET)
+        r = await client.post(
+            "/inara-nextcloud-talk-webhook",
+            content=body,
+            headers={**headers, "Content-Type": "application/json"},
+        )
+    assert r.status_code == 200
+
+
+# ---------------------------------------------------------------------------
+# Google Chat
+# ---------------------------------------------------------------------------
+
+_GCHAT_PAYLOAD = {
+    "chat": {
+        "messagePayload": {
+            "message": {"text": "Hello", "argumentText": "Hello"},
+            "space": {"name": "spaces/test123", "type": "ROOM"},
+        },
+        "user": {"displayName": "Test User"},
+    }
+}
+
+
+@pytest.mark.anyio
+async def test_gchat_no_audience_configured(client, mock_llm):
+    """When audience is not set, JWT check is skipped (current behaviour — documented bypass)."""
+    with patch("config.settings.google_chat_audience", ""):
+        r = await client.post("/channels/google-chat", json=_GCHAT_PAYLOAD)
+    # Should process the message (no auth enforcement when audience is empty)
+    assert r.status_code == 200
+
+
+@pytest.mark.anyio
+async def test_gchat_missing_token_with_audience(client):
+    """When audience IS configured, requests without a token must be rejected."""
+    with patch("config.settings.google_chat_audience", "123456789"):
+        r = await client.post("/channels/google-chat", json=_GCHAT_PAYLOAD)
+    assert r.status_code == 401
+
+
+@pytest.mark.anyio
+async def test_gchat_invalid_token_with_audience(client):
+    """A fake token should fail JWT verification."""
+    payload_with_token = {
+        **_GCHAT_PAYLOAD,
+        "authorizationEventObject": {"systemIdToken": "not.a.valid.jwt"},
+    }
+    with patch("config.settings.google_chat_audience", "123456789"):
+        r = await client.post("/channels/google-chat", json=payload_with_token)
+    assert r.status_code == 401
+
+
+@pytest.mark.anyio
+async def test_gchat_added_to_space(client, mock_llm):
+    """Bot added to a space — should return a greeting, no auth when audience empty."""
+    payload = {"chat": {"addedToSpacePayload": {"space": {"type": "ROOM"}}}}
+    with patch("config.settings.google_chat_audience", ""):
+        r = await client.post("/channels/google-chat", json=payload)
+    assert r.status_code == 200
+    assert "hostAppDataAction" in r.json()