Manifest Overview (Grid), Refined

[tomcrane]

Refinement of #70

Acceptance

• The sizes of the thumbnails can be adjusted, down to very small (many hundreds on screen together)
• You can select multiple canvases - doing so does not select anything for editing on the right
• You can drag single canvases to different places, thus re-ordering the canvas list
• You can drag multiple canvases to different places, thus re-ordering the canvas list
• Canvases have a right-click menu (with alternative mechansim for accessing) - send to start, send to end
• This works on selections, too

Notes

There is probably something here we can turn into the Range Editor, later.

[tomcrane]

To re-arrange canvases in Vault, at the moment you just set the items property of the manifest with the reordered canvas list.

In future we could optimise this with additional API for in-place rearrangement.

[tomcrane]

(MVP for this refined version - get single selection working first)

[tomcrane]

Going to close this and make a new grid view base issue

[tomcrane]

Superseded by #228