nuxt-studio

Port a legacy MDC-based PR onto the new comark-based `main`. Use when a contributor's PR was opened against the old `@nuxtjs/mdc` API (any commit before `feat(mdc): comark migration #355`) and now needs to be rebased / merged with the current Nuxt Studio main branch, which uses `comark` everywhere.

Converts hardcoded Vue components in a Nuxt Content markdown file into slot-based, Studio-editable MDC components. Use when a user wants their Nuxt Content page to be visually editable in Nuxt Studio's TipTap editor.