0.5.7 added the rotation API + programmatic nav actions on the
engine and wired the canvas handle's public proxy
(`controller.setRotation(deg)` / `controller.zoomIn()` / etc.) —
but `mountFrescoCanvas`'s controller layer in between forgot to
re-export the engine methods. Result: every call to
`handle.setRotation(...)` / `getRotation()` / `rotateBy()` /
`zoomIn()` / `zoomOut()` / `toggleFullscreen()` / `requestHome()`
on a <Fresco.canvas> handle threw
`TypeError: controller.X is not a function`.

Fresco's built-in `Rotate 90°` nav button (and the other built-in
buttons) called the engine directly and were unaffected.
Viewer-handle calls were also unaffected — viewer's handle IS
the controller, no intermediate layer.

Same family of leak 0.5.6 fixed for `setHomeAction` /
`setPanBounds` / `getTransform`. The controller now re-exports
every engine method the public handle proxies through.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>