fix(lint): resolve pyright and pylint issues in provider/backend changes

- Remove unused Bottle import from docker/backend.py (pyright)
- Suppress wrong-import-position on circular-import-avoiding
  deferred imports in backend/__init__.py (pylint C0413)
- Add encoding="utf-8" to read_text() in smolmachines provision
  test (pylint W1514)
- Suppress consider-using-with on TemporaryDirectory setUp pattern
  in both provision test files (pylint R1732)

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

tests/unit/test_docker_provision_git_user.py

@@ -120,7 +120,7 @@ def _git_config_exec_calls(bottle: MagicMock) -> list[tuple[str, str]]:
 
 class TestProvisionGitUser(unittest.TestCase):
     def setUp(self):
-        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-git-user.")
+        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-git-user.")  # pylint: disable=consider-using-with
         self.stage = Path(self._tmp.name)
 
     def tearDown(self):

tests/unit/test_smolmachines_provision.py

@@ -254,7 +254,7 @@ class TestProvisionCA(unittest.TestCase):
     cp_in + exec in the right order."""
 
     def setUp(self):
-        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-ca.")
+        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-ca.")  # pylint: disable=consider-using-with
         self.tmp = Path(self._tmp.name)
         self.egress_ca = self.tmp / "egress-ca.pem"
         _write_self_signed_cert(self.egress_ca)
@@ -346,7 +346,7 @@ class TestProvisionGit(unittest.TestCase):
     when its condition doesn't hold."""
 
     def setUp(self):
-        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-git.")
+        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-git.")  # pylint: disable=consider-using-with
         self.stage = Path(self._tmp.name)
 
     def tearDown(self):
@@ -407,7 +407,7 @@ class TestProvisionGit(unittest.TestCase):
         cp_call = bottle.cp_in.call_args
         staged_path = Path(cp_call.args[0])
         self.assertEqual(self.stage, staged_path.parent)
-        content = staged_path.read_text()
+        content = staged_path.read_text(encoding="utf-8")
         self.assertIn(
             '[url "http://127.0.0.1:9418/bot-bottle.git"]', content,
         )
@@ -507,7 +507,7 @@ class TestProvisionGitUser(unittest.TestCase):
 
 class TestProvisionWorkspace(unittest.TestCase):
     def setUp(self):
-        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-workspace.")
+        self._tmp = tempfile.TemporaryDirectory(prefix="cb-prov-workspace.")  # pylint: disable=consider-using-with
         self.stage = Path(self._tmp.name)
 
     def tearDown(self):