Migrate the last remaining V1 node (VACEOutpaint) to the V3 io.ComfyNode
API and register it in get_node_list(). The Python change is mechanical;
the stdlib io import is aliased to _io to avoid clashing with comfy's io.
Rewrite the JS node-sizing for Nodes 2.0. The old onResize/computeSize
hack inverted the V3 sizing model and caused runaway vertical growth on
horizontal drag. Drive height via the getMinHeight option with a flex
column that lets the canvas absorb extra height. There is no working
min-width channel for DOM widgets in Nodes 2.0, so contain the controls
with CSS (overflow:hidden, wrap/scroll rows) instead of forcing a floor.
Add V3_DOC_GAPS.md documenting the V3/Nodes 2.0 gaps hit during migration.