feat(docs): rename mcp.md to index.md and update sidebar referencesfeat(docs): restructure MCP documentation

Author: phodal

docs/mcp/mcp.md renamed to docs/mcp/index.md

@@ -144,8 +144,8 @@ const sidebars = {
 			type: 'category',
 			label: 'MCP',
 			items: [
+				'mcp/index',
 				'mcp/development',
-				'mcp/mcp',
 				'mcp/mcp-client',
 				'mcp/mcp-debugger',
 				'mcp/mcp-server',