fix: correct broken test assertions and exclude .agents templates from lint

Three test assertions had 'MINIMAL' string instead of 0, causing comparison
failures. Also exclude .agents/skills/ template files from ruff to fix
invalid-syntax errors caused by <placeholder> syntax in templates.

Author: partarstu

ruff.toml

@@ -21,6 +21,7 @@ exclude = [
     "allure-results",
     "local_models",
     ".agent",
+    ".agents",
 ]
 
 [lint]

tests/common/test_attachment_handler.py

@@ -164,7 +164,7 @@ def test_skip_files_with_postfix(self, mock_fetch_bytes):
 
         result = attachment_handler.fetch_all_attachments(["path/to/image_SKIP.png"])
 
-        assert len(result) == "MINIMAL"
+        assert len(result) == 0
         mock_fetch_bytes.assert_not_called()
 
     @patch.object(attachment_handler, "_fetch_file_bytes")
@@ -175,7 +175,7 @@ def test_skip_unsupported_mime_types(self, mock_fetch_bytes):
 
         result = attachment_handler.fetch_all_attachments(["path/to/archive.zip"])
 
-        assert len(result) == "MINIMAL"
+        assert len(result) == 0
 
     @patch.object(attachment_handler, "_fetch_file_bytes")
     @patch.object(attachment_handler.config, "JIRA_ATTACHMENT_SKIP_POSTFIX", "_SKIP")
@@ -204,7 +204,7 @@ def test_handle_fetch_errors_gracefully(self, mock_fetch_bytes):
 
         result = attachment_handler.fetch_all_attachments(["path/to/missing.png"])
 
-        assert len(result) == "MINIMAL"
+        assert len(result) == 0
 
     def test_empty_attachment_list(self):
         """Test empty attachment list returns empty result."""