fusion/.changeset/multi-project-migration.md

@gsxdsm/fusion

@gsxdsm/fusion
minor

Add migration and first-run experience for multi-project support

• Auto-detect and register existing projects on first run after upgrade
• Maintain backward compatibility for single-project workflows
• Interactive first-run setup wizard in dashboard
• Add fn init command for initializing new projects
• Add /api/setup-state and /api/complete-setup dashboard endpoints
• Idempotent migration — safe to re-run
• Rollback procedure documented in AGENTS.md