feat(api): Add preview endpoint

[tatarco]

What changed? Why was the change needed?

We need a quick stateless preview endpoint in order to have a single point or rendering for all workflows type.
what was done?

1. full flow controller -> hydration -> validation -> render for the preview endpoint.
2. move new V2 DTO's to a shared-internal package allowing the creation of clients for the FE to use as well as out E2E

https://www.loom.com/share/a3041ae59a9843bf98bb98829ca12a56?sid=6ac0f038-6c1e-4d5c-81c1-2761b7df5977

Screenshots

Expand for optional sections

Related enterprise PR

Special notes for your reviewer

[netlify]

✅ Deploy Preview for novu-stg-vite-dashboard-poc ready!

Name	Link
🔨 Latest commit	655b1a2
🔍 Latest deploy log	https://app.netlify.com/sites/novu-stg-vite-dashboard-poc/deploys/671778394a7efc0008a546c2
😎 Deploy Preview	https://deploy-preview-6648--novu-stg-vite-dashboard-poc.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[pkg-pr-new]

Open in Stackblitz

@novu/client

pnpm add https://pkg.pr.new/novuhq/novu/@novu/client@6648

@novu/headless

pnpm add https://pkg.pr.new/novuhq/novu/@novu/headless@6648

@novu/framework

pnpm add https://pkg.pr.new/novuhq/novu/@novu/framework@6648

@novu/js

pnpm add https://pkg.pr.new/novuhq/novu/@novu/js@6648

@novu/nest

pnpm add https://pkg.pr.new/novuhq/novu/@novu/nest@6648

@novu/node

pnpm add https://pkg.pr.new/novuhq/novu/@novu/node@6648

@novu/nextjs

pnpm add https://pkg.pr.new/novuhq/novu/@novu/nextjs@6648

@novu/notification-center

pnpm add https://pkg.pr.new/novuhq/novu/@novu/notification-center@6648

novu

pnpm add https://pkg.pr.new/novuhq/novu@6648

@novu/providers

pnpm add https://pkg.pr.new/novuhq/novu/@novu/providers@6648

@novu/react-native

pnpm add https://pkg.pr.new/novuhq/novu/@novu/react-native@6648

@novu/react

pnpm add https://pkg.pr.new/novuhq/novu/@novu/react@6648

@novu/shared

pnpm add https://pkg.pr.new/novuhq/novu/@novu/shared@6648

@novu/stateless

pnpm add https://pkg.pr.new/novuhq/novu/@novu/stateless@6648

commit: 655b1a2

[rifont]

Amazing work @tatarco ! 🚢 it