fix: resolve cross-platform test failures on Windows and Ubuntu

- Add proper cross-platform path handling with Path.resolve()
- Fix file encoding issues by explicitly using UTF-8
- Correct mock paths to use google.generativeai instead of gemini_server.genai
- Create setup.py for proper package installation in CI
- Add conftest.py with Windows asyncio compatibility
- Update CI workflow to install package with pip install -e .
- Add import tests to verify package installation
- Set PYTHONPATH in test environment
- Simplify import mechanism in tests

These changes ensure tests pass consistently across Windows, Ubuntu, and macOS platforms.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

tests/test_gemini_server.py

@@ -14,8 +14,7 @@ parent_dir = Path(__file__).resolve().parent.parent
 if str(parent_dir) not in sys.path:
     sys.path.insert(0, str(parent_dir))
 
-try:
-    from gemini_server import (
+from gemini_server import (
     GeminiChatRequest,
     CodeAnalysisRequest,
     read_file_content,
@@ -25,27 +24,6 @@ try:
     DEVELOPER_SYSTEM_PROMPT,
     DEFAULT_MODEL
 )
-except ImportError as e:
-    # If import fails, try alternative import method
-    import importlib.util
-    spec = importlib.util.spec_from_file_location(
-        "gemini_server", 
-        parent_dir / "gemini_server.py"
-    )
-    gemini_server = importlib.util.module_from_spec(spec)
-    sys.modules["gemini_server"] = gemini_server
-    spec.loader.exec_module(gemini_server)
-    
-    from gemini_server import (
-        GeminiChatRequest,
-        CodeAnalysisRequest,
-        read_file_content,
-        prepare_code_context,
-        handle_list_tools,
-        handle_call_tool,
-        DEVELOPER_SYSTEM_PROMPT,
-        DEFAULT_MODEL
-    )
 
 
 class TestModels:

tests/test_imports.py

@@ -0,0 +1,45 @@
+"""
+Test that imports work correctly when package is installed
+This helps verify CI setup is correct
+"""
+
+import pytest
+
+
+def test_direct_import():
+    """Test that gemini_server can be imported directly"""
+    try:
+        import gemini_server
+        assert hasattr(gemini_server, 'GeminiChatRequest')
+        assert hasattr(gemini_server, 'CodeAnalysisRequest')
+        assert hasattr(gemini_server, 'handle_list_tools')
+        assert hasattr(gemini_server, 'handle_call_tool')
+    except ImportError as e:
+        pytest.fail(f"Failed to import gemini_server: {e}")
+
+
+def test_from_import():
+    """Test that specific items can be imported from gemini_server"""
+    try:
+        from gemini_server import (
+            GeminiChatRequest,
+            CodeAnalysisRequest,
+            DEFAULT_MODEL,
+            DEVELOPER_SYSTEM_PROMPT
+        )
+        assert GeminiChatRequest is not None
+        assert CodeAnalysisRequest is not None
+        assert isinstance(DEFAULT_MODEL, str)
+        assert isinstance(DEVELOPER_SYSTEM_PROMPT, str)
+    except ImportError as e:
+        pytest.fail(f"Failed to import from gemini_server: {e}")
+
+
+def test_google_generativeai_import():
+    """Test that google.generativeai can be imported"""
+    try:
+        import google.generativeai as genai
+        assert hasattr(genai, 'GenerativeModel')
+        assert hasattr(genai, 'configure')
+    except ImportError as e:
+        pytest.fail(f"Failed to import google.generativeai: {e}")