feat(m9): systemd --user trigger modes + game-launch watcher — 0.23.0

D6 trigger modes, no root:
- core/service.py: write/enable `systemd --user` units; apply_mode(manual/
  always-on/game-launch) reconciles the recorder + watcher services; status().
- core/watcher.py + `rigdoctor watch`: poll Steam RunningAppID, auto-bracket a
  focused capture (D12 zero-config fallback; wrapper stays primary).
- CLI `rigdoctor service status|mode`; config `trigger_mode`.
- GUI Settings: "Recording trigger" dropdown (Apply runs apply_mode off-thread).
- Tests for unit generation, mode reconciliation, watcher transitions/parse.

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

tests/test_watcher.py

@@ -0,0 +1,69 @@
+"""Tests for the M9/D12 game-launch watcher (RunningAppID parse + transitions)."""
+
+import tempfile
+import unittest
+from pathlib import Path
+from unittest import mock
+
+from rigdoctor.core import watcher
+
+_REGISTRY = """"Registry"
+{
+\t"HKCU"
+\t{
+\t\t"Software"
+\t\t{
+\t\t\t"Valve"
+\t\t\t{
+\t\t\t\t"Steam"
+\t\t\t\t{
+\t\t\t\t\t"RunningAppID"\t\t"%s"
+\t\t\t\t}
+\t\t\t}
+\t\t}
+\t}
+}
+"""
+
+
+class TransitionTests(unittest.TestCase):
+    def test_transitions(self):
+        self.assertEqual(watcher.transition(0, 570), "start")
+        self.assertEqual(watcher.transition(570, 0), "stop")
+        self.assertIsNone(watcher.transition(570, 570))
+        self.assertIsNone(watcher.transition(0, 0))
+
+
+class FindKeyTests(unittest.TestCase):
+    def test_case_insensitive_nested(self):
+        data = {"Registry": {"HKCU": {"steam": {"runningappid": "42"}}}}
+        self.assertEqual(watcher._find_key(data, "RunningAppID"), "42")
+
+    def test_missing(self):
+        self.assertIsNone(watcher._find_key({"a": {"b": "c"}}, "RunningAppID"))
+
+
+class RunningAppIdTests(unittest.TestCase):
+    def _with_registry(self, content):
+        d = tempfile.mkdtemp()
+        path = Path(d) / "registry.vdf"
+        path.write_text(content)
+        return path
+
+    def test_reads_running_appid(self):
+        path = self._with_registry(_REGISTRY % "570")
+        with mock.patch.object(watcher, "_registry_path", return_value=path):
+            self.assertEqual(watcher.running_appid(), 570)
+
+    def test_zero_when_idle(self):
+        path = self._with_registry(_REGISTRY % "0")
+        with mock.patch.object(watcher, "_registry_path", return_value=path):
+            self.assertEqual(watcher.running_appid(), 0)
+
+    def test_zero_when_no_registry(self):
+        with mock.patch.object(watcher, "_registry_path", return_value=None):
+            self.assertEqual(watcher.running_appid(), 0)
+
+
+if __name__ == "__main__":
+    unittest.main()