Remove unused options for excluded types

[emcfarlane]

This is an optimization to remove unused options from the filtered file descriptor. These options aren't required in the image, the extension is excluded. We remove them to reduce the size of generated code.

Fixes https://github.com/bufbuild/buf/issues/3730

[github-actions[bot]]

The latest Buf updates on your PR. Results from workflow Buf CI / buf (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Aug 4, 2025, 4:54 PM

[bhollis]

Excited about this!

[bhollis]

I still think this would be cool