enhancement/issue 1218 native import attributes parsing

[thescientist13]

Related Issue

resolves #1218

Documentation

N / A

Summary of Changes

1. Upgrade to latest version of Acorn that now natively supports Import Attributes syntax
2. Upgrade to Rollup v4 and bump all relevant Rollup plugins (which now also supports import attributes in some plugin hooks!)
3. Add test cases to validate support for things like static and private class fields
4. Had originally tried fixing not all expected modern JavaScript syntax supported #1183 but to support all this across browser, API routes, and SSR page bundling, needed to make all these above upgrades anyway

TODO

1. Upstream this change to WCC and bump here - Import Attributes support in Acorn wcc#173
2. WCC also needs some help for processing new syntax - escodegen fails on Class fields usage wcc#174
3. should probably validate these changes in a downstream project or two, to be safe
4. track full import attributes support in Rollup - Rollup causes syntax error by changing valid code to invalid code (import attributes with -> assert) rollup/rollup#5685
5. archive / deprecate our custom fork - https://github.com/ProjectEvergreen/escodegen-esm