feat: add destination-labeled back button to Employee OnboardingExecutionFlow

[aaronlee777]

Summary

Adds a secondary back button above each step of the Employee onboarding execution flow. The label names the previous step (e.g. "Basic details" on Compensation, "Compensation" on Federal taxes) so users can orient themselves before clicking. The button is hidden on the initial profile step and on the final summary step.

When OnboardingExecutionFlow is rendered inside OnboardingFlow (the wrapper that owns the EmployeeList), the parent supplies an initialBackHeader so step one shows a "Back to employees" affordance and the user can exit the sub-flow at any time.

Changes

• New state-machine back-edges in onboardingExecutionStateMachine.ts mirroring the forward graph; deductions has a guarded fork that mirrors the self-onboarding path.
• New componentEvents.EMPLOYEE_ONBOARDING_BACK so the back event doesn't collide with CANCEL bubbling.
• New initialBackHeader prop on OnboardingExecutionFlow + initialHeader context field so the first-step header survives navigation back to it.
• New translations namespace Employee.OnboardingExecutionFlow with flat step-label keys + useI18n registration at the flow root.
• Extracted createBackHeaderFactory to src/components/Flow/useFlow.ts and documented the pattern in src/components/Flow/README.md so Company Onboarding (and any future linear flow) can adopt it cheaply.
• Fixed a stale-namespace bug in FlowHeader: useTranslation(ns) caches the namespace on first render and doesn't re-bind when the prop changes between steps. Switched to useTranslation() + per-call t(key, { ns }).

Demo

Related

Testing

• npm run test -- --run src/components/Employee/OnboardingExecutionFlow src/components/Employee/OnboardingFlow src/components/Flow — 48 tests pass, including 22 new state-machine tests covering destination labels, the guarded deductions back fork, and the initialHeader preservation across BACK.
• Manual: walk forward through the onboarding flow in the SDK dev app and confirm the back button on each step reads the previous step's name. From step one, click "Back to employees" and confirm it returns to the EmployeeList. Click back from Compensation → Profile; the parent's "Back to employees" header should re-appear.
• npx tsc --noEmit — clean.

🤖 Generated with Claude Code

[serikjensen]

This is a good first draft! i think we may need to further consider how back navigation can exist with breadcrumbs, progress indicator. Ironing out those cases would be a good candidate for design to implement in the sandbox

For the implementation, i think this is likely one we just need to ticket for the dev team. The biggest thing i'm thinking about is how to get back navigation working when you have nested flows. Ex. payroll execution flow is embedded in payroll flow. employee onboarding flow is nested inside of company onboarding flow.