[Vuex] Vuex 5

[kiaking]

Summary

Introducing a brand new Vuex for Vue 3. It's designed to improve various architecture and API of Vuex from what we've learned from past years. Here are the key differentiators from Vuex 3 & 4.

• 2 syntax support for the store creation, options api, and composition api.
• No mutations. Only state, getters, and actions.
• No nested modules. Only stores. Compose them instead.
• Complete TypeScript support.
• Transparent, automated code splitting.

Links

• Full Rendered Proposal
• Discussion Thread

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Important: Do NOT comment on this PR. Please use the discussion thread linked above to provide feedback, as it provides branched discussions that are easier to follow. This also makes the edit history of the PR clearer.

[kiaking]

We're closing this RFC due to Pinia becoming the next official state management lib for Vue.

Pinia has almost the exact same or enhanced API as Vuex 5, described in this RFC. You could simply consider Pinia as Vuex 5 with a different name.

[maxdzin]

Using pinia for a long time and it works like a charm! Thanks so much for such a great lib and your efforts, guys!