feat(tiptap): add meta.slashCommand to filter tiptap built-ins

[TotomInc]

Add meta.slashCommand to filter built-in tiptap sections (insert, style): allow fine-grained filtering or disabling entire sections.

---

Given the following slashCommand setup:

export default defineNuxtConfig({
  studio: {
    meta: {
      slashCommand: {
        exclude: ['heading4', 'code', 'codeBlock', 'bulletList', 'orderedList', 'blockquote', 'horizontalRule', 'strike'],
      },
    },
  },
})

---

Closes #373

[vercel]

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[pkg-pr-new]

npm i https://pkg.pr.new/nuxt-studio@421

commit: 650bd73