feat(cli): add --timeout flag to demo command

[manikantavarma2889]

Summary

• Added the --timeout <ms> option to the demo command to support configurable timeouts for built-in or discovered MCP servers.
• Passes timeoutMs to runTarget() via the target config, defaulting to 15000ms when the flag is omitted.
• Invalid non-number values throw a clear validation error.

Code of Conduct

By submitting this pull request, you agree to follow the project's Contributor Covenant Code of Conduct.

Validation

• npm run lint
• npm run typecheck
• npm test (Verified default/custom timeout and invalid value validation in tests/demo-command.test.ts)
• npm run smoke

Artifact Impact

• No artifact schema changes.
• No changes to the Markdown report formatting.

[manikantavarma2889]

The CI linter step is currently failing because the workflow uses pull_request_target, which checks out and installs the base main branch's incompatible typescript@7.0.2 dependency.

The changes in this PR include a downgrade to typescript@5.9.2 and ESLint configuration updates, which resolve the linter crash. All tests and lint checks pass cleanly when run on this branch.