cloudflare
Support eager memory deallocation on hibernation
While formally not a memory leak, this reduces Wasm memory usage for durable objects subject to hibernation by eagerly freeing Wasm memory associated with the stale instance when a new instance is constructed.
Unfortunately this fails because destroying the last instance when a new instance is constructed doesn't work since it seems we support constructing multiple in the same isolate of a given durable object.
It turns out this requires upstream work to properly support, given the multi-DO handling.
An upstream change for an unload event is posted in https://github.com/cloudflare/workerd/pull/5211.