feat(transform): add transform session commands

editor/transform.ts

@@ -0,0 +1,16 @@
+import type { Rect, Vec2D } from "@core/geometry";
+import type { ArtboardId } from "@core/id";
+
+export type TransformHandle = "body" | "n" | "ne" | "e" | "se" | "s" | "sw" | "w" | "nw";
+
+export type TransformTarget = {
+  type: "artboard";
+  id: ArtboardId;
+};
+
+export type TransformSession = {
+  target: TransformTarget;
+  handle: TransformHandle;
+  startPoint: Vec2D;
+  initialBounds: Rect;
+};