ability to override core system prompt (via .gemini/system.md) and specify core tools via coreTools setting (e.g. coreTools:["ls", "GrepTool", ...]) ; added tests, but did not update docs for now (#413)

packages/cli/src/config/config.ts

@@ -399,6 +399,7 @@ export async function loadCliConfig(settings: Settings): Promise<Config> {
     debugMode,
     argv.prompt || '',
     argv.all_files || false,
+    settings.coreTools || undefined,
     settings.toolDiscoveryCommand,
     settings.toolCallCommand,
     settings.mcpServerCommand,