Stepper Migration: Add user step to the hosting flow

[ddc22]

Related to #

Proposed Changes

• Brings the user step to the stepper framework with minimal changes
• Introduces a new temporary flow new-hosted-site-user-included to experiment with adding the user step to the hosting flow without breaking the existing implementation
• The new flow is added behind a feature flag onboarding/user-on-stepper-hosting if landed on flow without feature flag, the user will be redirected to new-hosted-site flow
• Raises the error handling of the <PasswordlessSignupForm /> component so that consuming client code can implement redirect side effects either with page.js or any other preferred mechanism.
• This change is merged prematurely since its hard to test flows locally.

Why are these changes being made?

• User on stepper is a critical step in completing the migration from signup to stepper completely.

Testing Instructions

Scenarios

• Login with new email by entering manually, makes sure user is logged in
• Login with exisitng email --> redirect to login ---> after login make sure the user redirects
• Login with existing user and go back, the user step should show the logged in user

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-aUh-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-108309

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-108309&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-108309&env=a8c-for-agencies

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

App Entrypoints (~2930 bytes added 📈 [gzipped])

name                   parsed_size           gzip_size
entry-stepper               +917 B  (+0.0%)     +298 B  (+0.1%)
entry-subscriptions         +750 B  (+0.0%)     +239 B  (+0.0%)
entry-domains-landing       +750 B  (+0.1%)     +239 B  (+0.1%)
entry-browsehappy           +750 B  (+0.3%)     +239 B  (+0.3%)
entry-main                  +728 B  (+0.0%)     +256 B  (+0.0%)
entry-login                 +630 B  (+0.0%)    +2871 B  (+0.7%)

Common code that is always downloaded and parsed every time the app is loaded, no matter which route is used.

Sections (~15152 bytes added 📈 [gzipped])

name                                parsed_size           gzip_size
new-hosted-site-flow-user-included      +7419 B    (new)    +2332 B    (new)
accept-invite                           +2553 B  (+1.3%)     +535 B  (+1.0%)
jetpack-connect                         +2493 B  (+0.2%)     +542 B  (+0.2%)
new-hosted-site-flow                     +147 B  (+1.8%)      +26 B  (+1.0%)
signup                                   +121 B  (+0.0%)      +18 B  (+0.0%)
update-design-flow                        +76 B  (+0.0%)       +4 B  (+0.0%)
link-in-bio-tld-flow                      +76 B  (+0.0%)       +4 B  (+0.0%)
devdocs                                   +48 B  (+0.0%)      +20 B  (+0.0%)
themes                                    +45 B  (+0.0%)      +19 B  (+0.0%)
theme                                     +45 B  (+0.0%)      +19 B  (+0.0%)
sites-dashboard                           +45 B  (+0.0%)      +14 B  (+0.0%)
site-monitoring                           +45 B  (+0.0%)      +14 B  (+0.0%)
settings                                  +45 B  (+0.0%)      +17 B  (+0.0%)
plugins                                   +45 B  (+0.0%)      +21 B  (+0.0%)
plans                                     +45 B  (+0.0%)      +68 B  (+0.0%)
marketplace                               +45 B  (+0.0%)      +20 B  (+0.0%)
jetpack-app                               +45 B  (+0.0%)      +13 B  (+0.0%)
hosting                                   +45 B  (+0.0%)      +14 B  (+0.0%)
home                                      +45 B  (+0.0%)      +19 B  (+0.0%)
github-deployments                        +45 B  (+0.0%)      +14 B  (+0.0%)
domains                                   +45 B  (+0.0%)      +19 B  (+0.0%)
dev-tools-promo                           +45 B  (+0.0%)      +14 B  (+0.0%)
checkout                                  +45 B  (+0.0%)      +19 B  (+0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Async-loaded Components (~1337 bytes added 📈 [gzipped])

name                                                                              parsed_size           gzip_size
async-load-signup-steps-user                                                          +2553 B  (+1.6%)     +584 B  (+1.3%)
async-load-design-blocks                                                               +181 B  (+0.0%)     +671 B  (+0.1%)
async-load-purchase-modal-wrapper                                                       +45 B  (+0.0%)      +12 B  (+0.0%)
async-load-my-sites-checkout-purchase-modal-is-eligible-for-one-click-checkou...        +45 B  (+0.0%)      +17 B  (+0.0%)
async-load-design                                                                       +45 B  (+0.0%)      +16 B  (+0.0%)
async-load-calypso-layout-masterbar-checkout-tsx                                        +45 B  (+0.0%)      +18 B  (+0.0%)
async-load-calypso-layout-masterbar-checkout                                            +45 B  (+0.1%)      +17 B  (+0.1%)
async-load-calypso-blocks-editor-checkout-modal                                         +45 B  (+0.0%)      +18 B  (+0.0%)

React components that are loaded lazily, when a certain part of UI is displayed for the first time.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• blaze-dashboard
• editing-toolkit
• odyssey-stats
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug add/user-step-to-hosting-flow on your sandbox.

[ddc22]

I am merging these changes behind a feature flag so that I can investigate more deeply in production/wpcalypso. There is relatively low impact to previous change and the only risky change is done here where a callback was raised to the parent level to delegate error handling to the caller.

https://github.com/Automattic/wp-calypso/pull/90680/files#diff-4429c22f5c781fc067387f540b93e856a249701220c0e88e7e2adb1d8c36a181R1288-R1300

Please feel free to revert this change if there is any impactful breaking change. Also please feel free to leave a review which I can followup on immediately.