fix: never deduplicate expressions in templates

[Rich-Harris]

Fixes #15096. A shame to lose this optimisation, but it doesn't make a difference to the vast majority of apps, and correctness comes first.

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🦋 Changeset detected

Latest commit: 0d4e966

The changes in this PR will be included in the next version bump.

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Playground

pnpm add https://pkg.pr.new/svelte@15451