Add channel-aware release tooling and updater recovery

release_tests/test_launcher_update_cli.py

@@ -0,0 +1,38 @@
+from __future__ import annotations
+
+from contextlib import redirect_stderr
+import io
+import unittest
+
+from ptlinux.cli import build_parser
+
+
+class LauncherUpdateCliTests(unittest.TestCase):
+	def test_bare_rollback_uses_retained_previous_release(self) -> None:
+		arguments = build_parser().parse_args(["launcher-update", "--rollback"])
+		self.assertEqual(arguments.rollback, "")
+
+	def test_explicit_rollback_accepts_version_and_history_override(self) -> None:
+		arguments = build_parser().parse_args(
+			[
+				"launcher-update",
+				"--rollback",
+				"1.8.0",
+				"--history-url",
+				"https://updates.example.test/history.json",
+			]
+		)
+		self.assertEqual(arguments.rollback, "1.8.0")
+		self.assertEqual(
+			arguments.history_url,
+			"https://updates.example.test/history.json",
+		)
+
+	def test_rollback_remains_exclusive_with_check_and_verify(self) -> None:
+		parser = build_parser()
+		with redirect_stderr(io.StringIO()), self.assertRaises(SystemExit):
+			parser.parse_args(["launcher-update", "--rollback", "--check"])
+
+
+if __name__ == "__main__":
+	unittest.main()