feat(nuxt): Added feature flag composables

[geferon]

Problem

Currently the Nuxt module is pretty barebones, and one major feature of Posthog imo is feature flags, so I am creating a PR to add some useful composables starting with feature flags.

Changes

Added 4 Nuxt Composables:

• usePostHog(): posthog | undefined
• useFeatureFlagEnabled(flag: string): Ref<boolean | undefined>
• useFeatureFlagPayload(flag: string): Ref
• useFeatureFlagVariantKey(flag: string): Ref<string | boolean | undefined>

Release info Sub-libraries affected

Libraries affected

• All of them
• posthog-js (web)
• posthog-js-lite (web lite)
• posthog-node
• posthog-react-native
• @posthog/react
• @posthog/ai
• @posthog/nextjs-config
• @posthog/nuxt

Checklist

• Tests for new code
• Accounted for the impact of any changes across different platforms
• Accounted for backwards compatibility of any changes (no breaking changes!)
• Took care not to unnecessarily increase the bundle size

If releasing new changes

• Ran pnpm changeset to generate a changeset file
• Added the "release" label to the PR to indicate we're publishing new versions for the affected packages

[vercel]

@geferon is attempting to deploy a commit to the PostHog Team on Vercel.

A member of the Team first needs to authorize it.

[geferon]

I haven't created a changeset because I'm wondering if this should be a minor or a major bump.
Hope this is helpful...

[greptile-apps]

_{8 files reviewed, 3 comments}

_{Edit Code Review Agent Settings | Greptile}

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[geferon]

It would be nice if it would be checked out and merged, since this functionality would be nice Nuxt features to have

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.