Entry globs don't update with new files

Looks like when a glob pattern is used in the `entry` array, tsup needs to use a file watcher in dev mode to know when a new entry point is added (when a matching file is created).

Trace tsup's dev-mode handling of entry glob patterns and its file-watching behavior. Verify how newly created files matching an entry glob are detected, then confirm that creating such a file causes the entry points to update and the relevant dev build behavior to refresh.

Written by the indexing model from the issue text.