Renderers emit plain changes; asset packages own their history

@jolly-pixel/pixel-draw.renderer and @jolly-pixel/voxel.renderer no longer depend on this package. A pixel document emits an EditChange (command, origin, inverse, peer) and applies an undo command through applyStep(command); a voxel world reports the cells each write replaced to its recorders. Everything else moved to the asset package of each document: pixelEdits(), the pixel guards and the canvas histories in asset.pixel-art, VoxelEdits and the voxel guards in asset.voxel-map. ChangeSourceAdapter wraps a plain change source into a history source with receipts and basis.

VoxelDocument built its VoxelEdits unconditionally, so every game using the engine plugin shipped this package. receipts, basis and the peer refusal rules are collaboration policy, which belongs next to the sync client that writes the receipts.

Considered Options

• Keep history in the renderers. Every change to the guards or receipts was a major release of two public packages, and runtime bundles paid for editor undo.
• A private undo stack in the canvas. Two undo models again, with different answers to peer edits; 0001 removed that.

Consequences

• PixelArtCanvasOptions.history takes a PixelArtCanvasHistory the host builds, such as StandalonePixelHistory or SharedPixelHistory.
• A sync client and a history share one source per document: pixelEdits(document), or the VoxelEdits that VoxelSyncClient builds as sync.edits.
• The renderers' tests use this package only as a dev dependency.