Svelte 5: deconflict `frag`

[benmccann]

Describe the bug

The user's template can access the generated frag variable

Reproduction

https://svelte-5-preview.vercel.app/#H4sIAAAAAAAAAyWMQQrDIBBFryKzLnRvk0LP0elCzFikZhQdS4J49ypdvv94v4HzgQroZwM2O4GGR0pwATnThPKlIDS4xJrtXJZis0-ibGShQ1aEPW41EMIdGSWQqPgxp1qVy-Z9Q16u_2JqbtN15PE4Mu88baAlV-qv_gMShBxhjAAAAA==

Severity

annoyance

[benmccann]

I was submitting this from a bug report on Discord, but I'm not sure how much we care to fix it because I just noticed it only works if the user references frag as a global / leaves it undefined

[Rich-Harris]

we should fix it — all generated names should be deconflicted against globals