update instructions

Author: roger.yu

.github/chatmodes/GitHub Tools.chatmode.md

@@ -0,0 +1,5 @@
+---
+description: 'Description of the custom chat mode.'
+tools: ['changes', 'codebase', 'editFiles', 'extensions', 'fetch', 'findTestFiles', 'githubRepo', 'new', 'openSimpleBrowser', 'problems', 'runCommands', 'runNotebooks', 'runTasks', 'runTests', 'search', 'searchResults', 'terminalLastCommand', 'terminalSelection', 'testFailure', 'usages', 'vscodeAPI', 'github', 'figma', 'filesystem', 'pylance mcp server', 'activePullRequest', 'copilotCodingAgent', 'configurePythonEnvironment', 'getPythonEnvironmentInfo', 'getPythonExecutableCommand', 'installPythonPackage']
+---
+Define the purpose of this chat mode and how AI should behave: response style, available tools, focus areas, and any mode-specific instructions or constraints.