declare function type with named syntax

[ignatiusmb]

Used where possible to make the function distinguishable from the other properties when autocomplete is showing, also makes it consistent across the files

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🦋 Changeset detected

Latest commit: d6bdd5d

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@sveltejs/kit	Patch

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[dummdidumm]

Needs a changeset because it's public-facing, but I'm all for it. Waiting for others to chime in before merging this.