Lazy load examples command dependencies

[chrisx9z]

Summary

• remove the top-level Examples import from CLI command registration
• lazy-load the examples module only when build --check-examples or examples:check runs
• keep zile new from loading the examples module, which imports typescript

Fixes #46.

Testing

• git diff --check
• rg -n "Examples|typescript" src/internal/cli/commands.ts src/Cli.ts src/Examples.ts

I could not run the Bun test suite locally because this environment does not have Bun installed.