feat: expose variable window.EXCALIDRAW_ASSET_PATH to allow host define the path for excalidraw assets

[ad1992]

CSB is also working now, no more chunk errors 🎉 try here

No more webpack_public_path needed explicitly in the host and it will default to unpkg CDN if window.EXCALIDRAW_ASSET_PATH is not defined.

for #3061, #3013, #3060

I had tried this approach earlier but unfortunately, I was assigning webpack_public_path at the wrong place in entry.js :/.

This will make hosting the excalidraw assets for the host much easier as its now scoped down to just Excalidraw.

TODOS

• Test in non CRA
• Test in CRA
• Append content hash to excalidraw-assets so cache bursting happens when version update
• update changelog and readme
• Release version v0.4.0 🎉

[vercel]

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