fix: rewrite smart quotes logic

[Ocean-OS]

Closes #781. I'm not entirely sure on what first does, or if I'm using it correctly in the logic, but everything else should be good.

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[teemingc]

I'm not entirely sure on what first does

I think first is used to tell if we're in a complete sentence or substring. It's only being used when we're processing the shiki tokens token by token so that a substring such as example" that's part of a bigger string "an example" will get the right quotation direction.

[teemingc]

The new approach seems to error in cases where a title has a single quote character such as https://svelte.dev/docs/kit/images#Vite's-built-in-handling . It changes the single quote to a left single quote when it should be a right single quote as it is currently.

Possible edge cases we should account for:
a) Vite's built-in handling (right single quote)
b) "Vite's built-in handling" (smart double quotes with right single quote)
c) <script lang="ts"> (smart double quotes but in a single word)

I wonder if it's worth adding a unit test for this but I can see we don't have Vitest set up despite having a test command in the root package.json