feat: add thumbnail image for chart widget

[denysdovhan]

This needs to be merged after this: https://github.com/wix-private/wix-cli/pull/3013

Key points:

• The PR above contains an implementation for presets
• It also contains schema changes for presets
• It also has fixes to @wix/gena package for properly copying binary files (images) without breaking them

Anyway, this PR needs to be checked with the latest @wix/gena and latest wix-cli/create-app.

[denysdovhan]

create-app exposes randomUUID as generatePageID for templates. It doesn't make sense in this case, since we're not generating a pageId, but we actually need a randomUUID.

There are 2 ways to fix this (from my point of view):

1. Remove generatePageID from templates and replace it with randomUUID directly.
2. Expose additional method (name, for example, generateUniqueID) and keep it along the generatePageID.