Rename smartrun to geniusrun throughout the codebase

Updates the Go module path, cmd/smartrund -> cmd/geniusrund, the
smartrun-dev skill, .gitignore, and every reference in docs/CLAUDE.md
to match.

backend/internal/api/review.go

@@ -8,7 +8,7 @@ import (
 
 	"github.com/go-chi/chi/v5"
 
-	"smartrun/backend/internal/store"
+	"geniusrun/backend/internal/store"
 )
 
 // defaultReviewQueuePageSize matches the frontend's initial/incremental