TS type issue when combining script module, generics and snippets

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Describe the bug

Trying to pass in a generic type to a snippet when I have a <script module> in the same svelte file results in odd behaviour

All tested with typescript 5.9.3

Reproduction

This results in a typescript error of Cannot find name 'T'.ts(2304) type T = /*unresolved*/ any on the snip arg (note that a {@const} instead of arg also errors, type T is just not visible)

<script lang="ts" module></script>

<script lang="ts" generics="T">
	import type { Snippet } from "svelte";
	let { snip = defaultSnip }: { snip: Snippet<[T]> } = $props();
</script>

{#snippet defaultSnip(generic: T)}
	Hello
{/snippet}

Removing the <script lang="ts" module></script> makes the issue go away completely.

Referencing a value (any value, unrelated to the generic) from the component like this also makes the issue go away

<script lang="ts" module></script>

<script lang="ts" generics="T">
	import type { Snippet } from "svelte";
	let { snip = defaultSnip }: { snip: Snippet<[T]> } = $props();
	const text = "Hello"
</script>

{#snippet defaultSnip(generic: T)}
	{text}
{/snippet}

Logs

System Info

System:
    OS: macOS 15.6.1
    CPU: (8) arm64 Apple M2
    Memory: 571.47 MB / 24.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 24.4.1 - /opt/homebrew/bin/node
    npm: 11.4.2 - /opt/homebrew/bin/npm
    bun: 1.2.18 - ~/.bun/bin/bun
  Browsers:
    Chrome: 140.0.7339.214
    Safari: 18.6

Severity

blocking an upgrade