v4.0.0

• ⚠️ Expose the library as a ES module, dropping CommonJS support.
• ⚠️ Rewrite the codebase to use modern ES syntax (you can still transpile on your end to keep IE11 support).
• ⚠️ Make code generation generate ESM modules by default, with CommonJS available through --legacy mode.
• ⚠️ Overhaul code generation to write simpler code that's more compact and more susceptible to efficient minimization — instead of nested objects, the generated code has flat exports of read and write functions (see readme and test fixtures).
• Add TypeScript type check & first-class typings via JSDoc comments.
• Remove dependency on ieee754 package and use native DataView instead, which is faster and universally supported.
• Modernize dev tools (use Rollup instead of Browserify for UMD builds, ESLint 9+; in addition to an earlier switch from Tap to native Node test runner and coverage and to GitHub Actions from Travis).
• Fix writing of default oneof fields. #103 by @farwayer