More fixes for PR review feedback

Improves end-to-end extension integration tests such that the
'CODEQL_MCP_WORKSPACE' env var is passed to StdioClientTransport,
which ensures that the server's relative-path resolution uses a
deterministic diretory instead of depending upon the Extension
Host's working directory.

Author: data-douser

extensions/vscode/test/suite/mcp-prompt-e2e.integration.test.ts

@@ -71,8 +71,12 @@ suite('MCP Prompt Error Handling Integration Tests', () => {
 
     const serverPath = resolveServerPath();
 
+    const workspaceDir =
+      vscode.workspace.workspaceFolders?.[0]?.uri.fsPath ?? ext.extensionUri.fsPath;
+
     const env: Record<string, string> = {
       ...process.env as Record<string, string>,
+      CODEQL_MCP_WORKSPACE: workspaceDir,
       TRANSPORT_MODE: 'stdio',
     };
 

server/test/src/prompts/workflow-prompts.test.ts

@@ -1777,7 +1777,7 @@ describe('Workflow Prompts', () => {
       });
       const text = result.messages[0].content.text;
       expect(text).toContain('does not exist');
-      // Verify the warning contains the resolved absolute path
+      // Verify the warning mentions the provided queryPath value
       expect(text).toContain('nonexistent/query.ql');
     });