Svelte 5 and svelte-check 4.0.0: Kaboom!

[frederikhors]

I have this Svelte + Typescript code and after upgrading today to svelte-check@4.0.0 I get 149 errors like this:

• Select.svelte:

<script lang="ts">
    type SelectOption = {
        label: string;
        value?: string | number | boolean | null;
    };

    type Props = {
        id?: string;
        value?: SelectOption['value'];
        options: Array<SelectOption>;
        onChange?: (e: SelectOption['value']) => void;
    };

    let {
        id,
        value = $bindable(),
        options = [],
        onChange,
        ...props
    }: Props = $props();

    const handleOnChange = () => {
        onChange?.(value);
    };
</script>

<select
    {id}
    bind:value
    onchange={handleOnChange}
    {...props}
>
    {#each options as option}
        <option value={option.value}>{option.label}</option>
    {/each}
</select>

And I'm using it like this:

<script lang="ts">
    enum PlayerOrderBy {
        NameAsc = 'Name_ASC',
        NameDesc = 'Name_DESC',
    }

    let playerOrder = $state(PlayerOrderBy.NameAsc);
</script>

<Select bind:value={playerOrder} options={[]} />

but Typescript is giving me this error:

Type 'string | number | boolean | null' is not assignable to type 'PlayerOrderBy'.
  Type 'null' is not assignable to type 'PlayerOrderBy'.ts(2322)

Why?

I think a way I can fix it is using:

<Select bind:value={playerOrder as PlayerOrderBy} options={[]} />

But it does feel cheating to me...

Reproduction

NOTE: The REPL doesn't work for this reproduction, I don't know why.