feat: mark onboarding steps from CLI commands

[jomifepe]

Summary

• Extend src/clients/repository.ts with onboarding helpers (getOnboardingState, completeOnboardingSteps, completeOnboardingStepsSilently) wrapping the Repository Service's GET /onboarding and PATCH /onboarding/:stepId/toggle endpoints — same contract as slice-machine's PrismicRepositoryManager.
• Introduce an OnboardingStep union scoped to the dashboard's current set: createPrismicProject, createPageType, createSlice, connectPrismic.
• Fire each step from the command that actually performs the corresponding server-side action:
  • prismic repo create → createPrismicProject
  • prismic push → createSlice (when a slice is inserted remotely) and/or createPageType (when an inserted custom type has format: "page")
  • prismic pull and prismic sync (after initial sync) → connectPrismic
• All calls are fire-and-forget via the silent wrapper, so onboarding failures never block or noise up CLI commands. State is fetched first so already-completed steps aren't toggled off.

How to QA

• npx prismic@pr-178 repo create marks createPrismicProject (this is a self-completing step, but why not)
• npx prismic@pr-178 push after slice create marks createSlice complete
• npx prismic@pr-178 push after type create for page-format type marks createPageType; pushing a non-page type does not
• npx prismic@pr-178 pull marks connectPrismic complete
• npx prismic@pr-178 sync --watch marks connectPrismic on the initial sync
• Running any of the above twice does not un-complete a step (GET-before-PATCH guard)
• With a stale/missing token, commands still succeed silently

🤖 Generated with Claude Code

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