chore: bump to typescript 5.9

[jasonlyu123]

This adds support for the new hover length config. One thing that is caught by the test is that the "click" event is now "PointerEvent" instead of MouseEvent. This might need to be synced to svelte/elements later.

This also changes the typescript-plugin to add support for the two hover parameters. Including the one for expandable hover in ts/js files.

[jasonlyu123]

In case anyone is wondering, expandable hover won't be supported in the Svelte files any time soon. The VSCode API is experimental, it's also not supported by LSP, and even the TypeScript API is considered internal.

[varungandhi-src]

This PR causes a regression; it can cause a stack overflow, so svelte-check no longer works for our work codebase. Potentially related to this upstream issue: microsoft/TypeScript#62218

I'll see if we can provide a minimal reproducer upstream.

[jasonlyu123]

@varungandhi-src, it should be #2819. Can you check if your tsconfig.json has both references and include config? If so, check if the referenced project has the same include config as the main tsconfig.

Edit: Another situation is if you only have references and not include and files in your tsconfig.json, becuase that means include everything.