fix(editor): refresh framework state after onboarding changes

[DavidBabinec]

Summary

• Retain CMS site reload requests until the Site editor actually hydrates the fresh site document.
• Route framework/settings saves through the retained reload helper so dashboard and settings changes share the same behavior.
• Add regression coverage for a cancelled Site editor mount preserving the pending reload.

Root Cause

The pending CMS site reload flag was consumed before the async Site load resolved. If the persistence hook unmounted before hydration, the next mount treated the stale editor store as authoritative and skipped the refetch, so onboarding framework changes only appeared after a hard refresh.

Verification

• bun run build
• bun test (5863 pass, 0 fail)
• bun run lint
• Browser smoke: with a local SQLite dev server, Dashboard Core Framework remove/import reflected in the Site editor without a hard refresh.