Enable cache: no-cache compat flag and enum

[AdityaAtulTewari]

First part of cache: no-cache implementation:

• Work-shopping the test infrastructure in workerd.
• Allow no-cache construction
• Update typescript information

Note that the actual implementation is incompelete.

[fhanau]

I'll need some context here to review this well:

• Is the compat flag the right enabling mechanism here? Are there cases where supporting cache:no-store will be incompatible? Or is this just to support using it while it is not fully stable?
• Should this be landed while incomplete? Are there any internal PRs I should look out for?

[AdityaAtulTewari]

Is the compat flag the right enabling mechanism here? Are there cases where supporting cache:no-store will be incompatible? Or is this just to support using it while it is not fully stable?

There are no cases where cache: no-store will be incompatible, it is just for support while we conduct additional tests on the internal side. I intend to have the no-store flag, enable this flag after a certain compat date.

Should this be landed while incomplete? Are there any internal PRs I should look out for?

In the past this is how we did it because it allowed me to experiment with tests in live workers before we pushed this feature to customers. I think that this same principle of experimentation applies here. There are no internal PRs that are associated with this change yet.

[jasnell]

LGTM but let's be sure to test internally before merging

[github-actions]

The generated output of @cloudflare/workers-types has been changed by this PR. If this is intentional, run bazel build //types && rm -rf types/generated-snapshot && cp -r bazel-bin/types/definitions types/generated-snapshot to update the snapshot. Alternatively, you can download the full generated types: https://github.com/cloudflare/workerd/actions/runs/12344234285/artifacts/2323808138

Full Type Diff

diff -r bazel-bin/types/definitions/experimental/index.d.ts types/generated-snapshot/experimental/index.d.ts
1680c1680
<   cache?: "no-store" | "no-cache";
---
>   cache?: "no-store";
1694c1694
<   cache?: "no-store" | "no-cache";
---
>   cache?: "no-store";
diff -r bazel-bin/types/definitions/experimental/index.ts types/generated-snapshot/experimental/index.ts
1688c1688
<   cache?: "no-store" | "no-cache";
---
>   cache?: "no-store";
1702c1702
<   cache?: "no-store" | "no-cache";
---
>   cache?: "no-store";