Consider adding per-phase timing breakdown to azd up SUCCESS message

[jongio]

Summary

The azd up SUCCESS message currently shows a single total duration:

Your application was provisioned and deployed to Azure in 10 minutes 57 seconds.

It does not break down how much time was spent in each phase (provisioning vs packaging vs deploying). This would help users understand where time is being spent and identify optimization opportunities.

Proposal

Consider adding a per-phase timing breakdown, e.g.:

Your application was provisioned and deployed to Azure in 10 minutes 57 seconds.
  Provisioning: 9m 12s
  Deploying:    1m 45s

Or as a footer row in the deploy progress table.

Context

• The deploy progress table shows per-service Duration (publish+deploy time only)
• The SUCCESS message shows total wall clock (provision+deploy minus prompt time)
• There is currently no visibility into how long provisioning took vs deployment
• Related PR: feat(exegraph): graph-driven execution engine for up/provision/deploy #7776 (execution graph)
• Related issue: Deployment Times Does Not add up #7981 (deploy duration mismatch)

Considerations

• With the execution graph (azd up), packaging runs in parallel with provisioning — should package time be shown separately or folded in?
• For azd deploy (no provisioning), the breakdown would just show deploy time
• Should this be opt-in (verbose flag) or always shown?