feat: add isOrgStarter flag for org-level starter templates

[field123]

Summary

• Adds isOrgStarter boolean column to the Project entity with a DB migration
• Team editors (org admins) can toggle "Set as organization starter" on projects via the project context menu
• Org starters appear in the New Project modal across all workspaces in the same team
• Server-side permission check ensures only team editors can set the flag

Files changed

• Entity/Migration: New isOrgStarter column + migration
• ApiSchema: Added to ApiProject and SetSiteInfoReq
• routes/projects.ts: Include in API response
• DbMgr.ts: Updatable field + team editor permission check
• ProjectListItem.tsx: Context menu toggle (gated on team editor perms)
• NewProjectModal.tsx: "Organization starters" section in new project dialog

Test plan

• As team editor: toggle org starter on a project, verify it appears in New Project across all workspaces in the team
• As non-team-editor: verify the menu item is hidden
• Verify workspace starters continue to work independently
• Verify org starters from a different team are not shown