fix: redirect INFO/DEBUG logs to stderr for MCP protocol compliance #520
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Problem\nINFO/DEBUG log messages were written to stdout via "console.log()", which violates MCP's requirement that stdout contain only JSON-RPC messages. This caused JSON parse errors in Claude Desktop.\n\n## Solution\nRoute the default logger output to stderr instead of stdout by using "console.error()" in the logger's default case.\n\n## Testing\n- Verified stdout contains only JSON-RPC: \n "echo '{"jsonrpc":"2.0",...}' | node dist/mcp/index.js 2>/dev/null"\n- Verified log output appears on stderr: \n "echo '{"jsonrpc":"2.0",...}' | node dist/mcp/index.js 2>&1 1>/dev/null"