Implement cache batch upload using remote bindings

[vicb]

We use:

• native batch upload support for KV upload
• rclone for batch R2 upload

There are 2 problems with that.

First the cache population does not go through the cache handlers so we have duplicated logic.

The second issue is that R2 (which is the recommend cache store) can not use rclone in dev and is too slow there.

We should probably tackle that second issue first.

Notes:

• we can remove the R2 env vars when this is implemented
• it should significantly speed up e2e tests

[vicb]

As a first step we should use wrangler r2 bulk put implemented in cloudflare/workers-sdk#11285

Once cloudflare/workers-sdk#11253 is fixed, we can switch to remote binding and using the cache handler to populate the cache.

[vicb]

see #991