Build contribution calendar component on profile

What does this MR do and why?

Related to #378676 (closed)

In &9056 we are incrementally migrating the tabs on the profile from a mix of HAML/jQuery to full Vue.

This MR creates a Vue component for the contribution calendar and renders it in the Overview tab. It does not yet implement clicking on a day to see the specific activity. That is currently blocked by #378695 (closed) and will implemented in a separate MR.

Furthermore, since app/assets/javascripts/pages/users/activity_calendar.js is still required when the profile_tabs_vue feature flag is disabled we are keeping it for now and using it in the Vue component. Once we finish &9056 and remove the feature flag we can move that logic directly into app/assets/javascripts/profile/components/activity_calendar.vue and remove that file. This will be tracked in #393099

Screenshots or screen recordings

Desktop

profile_tabs_vue feature flag disabled	profile_tabs_vue enabled

Tablet

profile_tabs_vue feature flag disabled	profile_tabs_vue enabled

Mobile

profile_tabs_vue feature flag disabled	profile_tabs_vue enabled

How to set up and validate locally

1. Enable the profile_tabs_vue feature flag
   • bin/rails console
   • Feature.enable(:profile_tabs_vue)
2. Go to your profile

MR acceptance checklist

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