test: migrate from Jest to Vitest (Phase 1 complete)

- Remove Jest and all related packages
- Install Vitest with coverage support
- Create vitest.config.ts with path aliases
- Set up global test configuration
- Migrate all 6 test files to Vitest syntax
- Update TypeScript configuration for better Vitest support
- Create separate tsconfig.build.json for clean builds
- Fix all import/module issues in tests
- All 68 tests passing successfully
- Current coverage baseline: 2.45%

Phase 1 of testing suite improvement complete.

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

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

types/mcp.d.ts

@@ -0,0 +1,35 @@
+// Type declarations for MCP SDK responses
+declare module '@modelcontextprotocol/sdk/client/index.js' {
+  export * from '@modelcontextprotocol/sdk/client/index';
+  
+  export interface ToolsListResponse {
+    tools: Array<{
+      name: string;
+      description?: string;
+      inputSchema?: any;
+    }>;
+  }
+
+  export interface CallToolResponse {
+    content: Array<{
+      type: string;
+      text?: string;
+    }>;
+  }
+}
+
+declare module '@modelcontextprotocol/sdk/server/index.js' {
+  export * from '@modelcontextprotocol/sdk/server/index';
+}
+
+declare module '@modelcontextprotocol/sdk/server/stdio.js' {
+  export * from '@modelcontextprotocol/sdk/server/stdio';
+}
+
+declare module '@modelcontextprotocol/sdk/client/stdio.js' {
+  export * from '@modelcontextprotocol/sdk/client/stdio';
+}
+
+declare module '@modelcontextprotocol/sdk/types.js' {
+  export * from '@modelcontextprotocol/sdk/types';
+}