test(notifier): ✅ add tests for notifier module

tests/test_mail_reader.py

@@ -24,13 +24,13 @@ from logwatcher.mail_reader import (
 
 @pytest.fixture(name="empty_mail")
 def get_empty_mail_fixture() -> Message:
-    """A fake Message"""
+    """Return a fake Message."""
     return Message(subject="test without attachment", text_body="test")
 
 
 @pytest.fixture(name="log_mail_with_attachment")
 def get_log_mail_with_attachment(original_log_dir: Path) -> Message:
-    """A fake Message with a .txt file attachment."""
+    """Return a fake Message with a .txt file attachment."""
     file = original_log_dir / "CR_20260727110008.txt"
 
     return Message(
@@ -49,7 +49,7 @@ def get_log_mail_with_attachment(original_log_dir: Path) -> Message:
 
 @pytest.fixture(name="log_mail_with_body")
 def get_log_mail_with_body() -> Message:
-    """A fake Message with logs in text body."""
+    """Return a fake Message with logs in text body."""
     return Message(
         subject="test with logs in text body",
         text_body="Compte-rendu du suivi des imports NOSYMAG du 02/09/2026 à 15:00:10\n\n\n"
@@ -88,14 +88,14 @@ class FakeProtocol:
     """Protocol whose .version access raises UnauthorizedError."""
 
     @property
-    def version(self):
+    def version(self):  # noqa: D102
         raise UnauthorizedError("invalid credentials")
 
 
 class FakeAccount:
     """Account with a protocol that raises on version access."""
 
-    def __init__(self):
+    def __init__(self):  # noqa: D107
         self.protocol = FakeProtocol()
 
 
@@ -103,14 +103,14 @@ class OkProtocol:
     """Protocol whose .version succeeds."""
 
     @property
-    def version(self):
+    def version(self):  # noqa: D102
         return MagicMock()
 
 
 class OkAccount:
     """Account with a protocol that returns a version successfully."""
 
-    def __init__(self):
+    def __init__(self):  # noqa: D102
         self.protocol = OkProtocol()
 
 
@@ -154,10 +154,7 @@ def test_find_log_attachment_accepts_no_extension(empty_mail: Message):
 def test_find_log_attachment_rejects_other_names(
     empty_mail: Message,
 ):
-    """
-    Rejects attachments not starting with CR_ even with .txt
-    or .log extension or extensionless.
-    """
+    """Rejects attachments not starting with CR_ even with .txt or .log extension or extensionless."""
     attachments = (
         FileAttachment(
             name="attachment.pdf",