refactor: remove dead re-exports from cli.ts and unexport ExecaMockResult (#2992)

- Remove all 38 dead barrel re-exports from src/cli.ts that were
  added during the cli.ts split but never consumed via the cli module
  (all consumers import directly from the source modules)
- Remove deprecated DEFAULT_DNS_SERVERS re-export (all consumers
  import from dns-resolver.ts directly)
- Remove export keyword from ExecaMockResult interface in
  host-iptables-test-setup.ts (never imported outside its file)
- Update cli.test.ts to import copilot API functions from
  copilot-api-resolver.ts instead of the cli barrel

Closes #2991
Closes #2990

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: lpcox

src/cli.test.ts

@@ -23,7 +23,7 @@ import {
   deriveCopilotApiTargetFromProviderBaseUrl,
   deriveCopilotApiBasePathFromProviderBaseUrl,
   resolveCopilotApiRouting,
-} from './cli';
+} from './copilot-api-resolver';
 import { redactSecrets } from './redact-secrets';
 
 type MockedCommanderModule = typeof import('commander') & {

src/cli.ts

@@ -1,74 +1,5 @@
 #!/usr/bin/env node
 
-// Re-export domain utilities (extracted to domain-utils.ts)
-export {
-  parseDomains,
-  parseDomainsFile,
-  isValidIPv4,
-  isValidIPv6,
-  AGENT_IMAGE_PRESETS,
-  isAgentImagePreset,
-  validateAgentImage,
-  processAgentImageOption,
-  DEFAULT_OPENAI_API_TARGET,
-  DEFAULT_ANTHROPIC_API_TARGET,
-  DEFAULT_GEMINI_API_TARGET,
-  DEFAULT_COPILOT_API_TARGET,
-} from './domain-utils';
-
-// Re-export API proxy config (extracted to api-proxy-config.ts)
-export {
-  validateApiProxyConfig,
-  validateAnthropicCacheTailTtl,
-  validateApiTargetInAllowedDomains,
-  emitApiProxyTargetWarnings,
-  emitCliProxyStatusLogs,
-  warnClassicPATWithCopilotModel,
-  extractGhecDomainsFromServerUrl,
-  extractGhesDomainsFromEngineApiTarget,
-  resolveApiTargetsToAllowedDomains,
-} from './api-proxy-config';
-
-// Re-export option parsers (extracted to option-parsers.ts)
-export {
-  buildRateLimitConfig,
-  validateRateLimitFlags,
-  validateEnableOpenCodeFlag,
-  collectRulesetFile,
-  hasRateLimitOptions,
-  validateSkipPullWithBuildLocal,
-  validateAllowHostPorts,
-  validateAllowHostServicePorts,
-  applyHostServicePortsConfig,
-  parseMemoryLimit,
-  parseAgentTimeout,
-  applyAgentTimeout,
-  checkDockerHost,
-  resolveDockerHostPathPrefix,
-  parseDnsServers,
-  parseDnsOverHttps,
-  processLocalhostKeyword,
-  escapeShellArg,
-  joinShellArgs,
-  parseEnvironmentVariables,
-  parseVolumeMounts,
-  formatItem,
-} from './option-parsers';
-
-/**
- * Default DNS servers (Google Public DNS)
- * @deprecated Import from dns-resolver.ts instead
- */
-export { DEFAULT_DNS_SERVERS } from './dns-resolver';
-
-// Re-export for backwards compatibility (used by cli.test.ts and other consumers)
-export {
-  resolveCopilotApiKey,
-  deriveCopilotApiTargetFromProviderBaseUrl,
-  deriveCopilotApiBasePathFromProviderBaseUrl,
-  resolveCopilotApiRouting,
-} from './copilot-api-resolver';
-
 import { program } from './cli-options';
 import { createMainAction } from './commands/main-action';
 import { registerSubcommands } from './commands/subcommands';

src/test-helpers/host-iptables-test-setup.ts

@@ -10,7 +10,7 @@ jest.mock('../logger', () => require('./mock-logger.test-utils').loggerMockFacto
 type ExecaMockError = Error & { stderr?: string };
 type MockedExecaFn = (file: string, args?: readonly string[], options?: unknown) => Promise<ExecaMockResult>;
 
-export interface ExecaMockResult {
+interface ExecaMockResult {
   command: string;
   escapedCommand: string;
   exitCode: number;