feat: guided diagnostic session (CLI) — pick a game, capture, analyze — 0.11.0

The seed use case end to end, orchestrating M3 + M4 (ARCHITECTURE §7.1).

- core/diagnostic.py: start(game) runs a focused, game-tagged capture into a
  dedicated diagnostic log (window-scoped report, separate from the always-on
  crash log); finish() stops it and combines the capture summary (M3) with the
  health findings (M4). Game recorded as a log event so it survives crash+reboot.
- CLI: rigdoctor diagnose start --game/--appid | status | finish.
- recorder/record run gained an optional --game tag; reccontrol passes it through.
- Tests for game recovery + the finish() combination.

GUI/tray "Run Diagnostic" button and auto start/stop (D12 wrapper) come next.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/test_diagnostic.py

@@ -0,0 +1,61 @@
+"""Tests for the guided diagnostic orchestration (M3+M4 glue)."""
+
+import tempfile
+import time
+import unittest
+from pathlib import Path
+from unittest import mock
+
+from rigdoctor.core import diagnostic
+from rigdoctor.core.crashlog import CrashLogWriter, summarize
+from rigdoctor.core.health import Finding
+from rigdoctor.core.sample import Reading, Sample
+
+
+def _write_log(path: str, game: str) -> None:
+    w = CrashLogWriter(path)
+    w.write_event("session-start", "interval=1s")
+    w.write_event("game", game)
+    for temp in (60.0, 72.0, 81.0):
+        w.write_sample(Sample(ts=time.time(), readings=[Reading("gpu", "temp", temp, "°C", "")]))
+    w.write_event("gpu-lost", "nvidia-smi query timed out")
+    w.close()
+
+
+class GameRecoveryTests(unittest.TestCase):
+    def test_game_recovered_from_log_event(self):
+        with tempfile.TemporaryDirectory() as d:
+            log = str(Path(d) / "capture.jsonl")
+            _write_log(log, "Path of Exile 2")
+            summary = summarize(log)
+            self.assertEqual(diagnostic._game_from_summary(summary), "Path of Exile 2")
+
+    def test_no_game_event_returns_none(self):
+        with tempfile.TemporaryDirectory() as d:
+            log = str(Path(d) / "capture.jsonl")
+            w = CrashLogWriter(log)
+            w.write_event("session-start")
+            w.close()
+            self.assertIsNone(diagnostic._game_from_summary(summarize(log)))
+
+
+class FinishTests(unittest.TestCase):
+    def test_finish_combines_summary_and_findings(self):
+        with tempfile.TemporaryDirectory() as d:
+            log = Path(d) / "capture.jsonl"
+            _write_log(str(log), "Satisfactory")
+            fake = [Finding("warning", "GPU", "NVIDIA Xid 79 ×1", "fell off the bus")]
+            with mock.patch("rigdoctor.core.health.run_health_checks", return_value=fake), \
+                 mock.patch.object(diagnostic.reccontrol, "stop_background", return_value=False), \
+                 mock.patch.object(diagnostic.reccontrol, "running_pid", return_value=None):
+                result = diagnostic.finish(log_path=log)
+            self.assertEqual(result.game, "Satisfactory")
+            self.assertEqual(result.summary.samples, 3)
+            self.assertEqual(result.findings, fake)
+            # peak GPU temp captured in the window, GPU-lost event recorded
+            self.assertEqual(result.summary.maxima["gpu.temp"][0], 81.0)
+            self.assertTrue(any(kind == "gpu-lost" for _ts, kind, _d in result.summary.events))
+
+
+if __name__ == "__main__":
+    unittest.main()