Restore Trusted Types from BCD 6.0.24

[saschanaz]

Closes #1246

[github-actions[bot]]

Thanks for the PR!

This section of the codebase is owned by @saschanaz - if they write a comment saying "LGTM" then it will be merged.

[saschanaz]

Every feedback from #1246 applies here too.

[saschanaz]

Work item - Trusted* types should be ignored from the getter. And those types need to get the nominal type hack too. (Why in 2025 we still have no official solution for this? 😞)

[saschanaz]

Trusted* types should be ignored from the getter.

This needs TS5.1+ for https://github.com/microsoft/TypeScript/pull/53417. Meaning anyone with pre-5.1 will not be able to assign trusted types without any hack.

Edit: well, given we only have 5.5/5.6 backward-compat types, this effectively means pre-5.5 users would get problems. (I really don't want to add more unless it's super duper required)

[jakebailey]

Oh boy, I wonder how much this conflicts with the existing trusted types that people are using...

[saschanaz]

Should certainly take a look at https://www.npmjs.com/package/@types/trusted-types?activeTab=code to reduce friction.

[saschanaz]

Although the library's private brand: true effectively makes it exclusive to any other declaration AFAICT...

[jakebailey]

Although the library's private brand: true effectively makes it exclusive to any other declaration AFAICT...

Yeah, they are declared as classes, and that private brand means they are nominal. I think this is definitely something that needs to be rectified somehow...