fix: Fix 500 error due to undefined storage

[danielh-official]

Issue: #1938

Because #storage can be undefined, calling getItem as a function throws an error.

I've wrapped it in a try...catch block to return the fallback on catch.

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[Conduitry]

This doesn't sound right to me. If this.#storage were undefined, then this.#storage?.getItem(this.#key) would also be undefined, not throw an exception. The error you're getting in the linked issue sounds like this.#storage is not undefined, but it doesn't have a getItem method, and I don't know when that would happen.

[Conduitry]

Ah. localStorage was added as a global in Node 25, without needing the --experimental-webstorage flag. (nodejs/node#57666) But it's non-functional if you don't start Node with --localstorage-file. I expect just doing this.#storage?.getItem?.(this.#key) should work in this case. We'd still get the warning from Node the first time about needing to specify a file, but I don't have a good idea about how to handle that off the top of my head other than to also just check whether we're on the server or in a browser.

[teemingc]

closing in favour of #1941