fix: resolve import issues for PyPI platform tools

- Made feedparser import optional in discovery.py with graceful fallback
- Fixed GitHubClient import to use correct GitHubAPIClient class name
- Made server import optional in __init__.py to allow tool imports without fastmcp dependency
- Added warning when feedparser is not available for RSS functionality
- All tool modules now importable without external dependencies

This allows the MCP server to start even when optional dependencies are missing, providing graceful degradation of functionality.

pypi_query_mcp/__init__.py

@@ -8,6 +8,10 @@ __version__ = "0.1.0"
 __author__ = "Hal"
 __email__ = "hal.long@outlook.com"
 
-from pypi_query_mcp.server import mcp
-
-__all__ = ["mcp", "__version__"]
+try:
+    from pypi_query_mcp.server import mcp
+    __all__ = ["mcp", "__version__"]
+except ImportError:
+    # Server dependencies not available (fastmcp, etc.)
+    # Tools can still be imported individually
+    __all__ = ["__version__"]