Add loaders, rules, and plugins to dashboard

[codenickycode]

• react refresh plugin
• mini css extract loader
• style loader
• font rule
• image rule
• svg rule
• swc loader
• dot env plugin
• css loader
  • camelCase
• postcss-loader
  • autoprefixer

[codenickycode]

Code splitting:

DOM widget renders an async component using React.lazy. Asserts component loaded correctly.
Script imports dynamic chunk, asserts import succeeded
Validate prod/dev builds:

Script checks process.env.NODE_ENV value
Script compares build output file sizes
Unused CSS:

Script parses CSS bundles, asserts usage of each class/selector
DOM widget imports CSS, asserts measured styles after rendering
Environment vars:

Script asserts env vars replaced, e.g. process.env.API_KEY is defined
Tree shaking:

Script imports known unused code, asserts it's not included
DOM widget imports large utility library, checks bundle size
Content hashing:

Script fetches all asset files, checks hashes look correct
TypeScript types:

Script checks all tsconfig types are generated
DOM widgets tests importing .d.ts files
JSDoc comments:

Script parses output bundle, asserts JSDoc comments exist