Improve CI pipeline

[terrier989]

• Both dart2js and dart2wasm compilers should be tested.
• Adds a package analyzer job.
• Improves various other things.
• Runs formatting.

[Copilot]

Pull Request Overview

This PR enhances the CI/CD pipeline to improve code quality checks and test coverage. The changes ensure both dart2js and dart2wasm compilers are tested, add package health analysis, and improve code formatting consistency across the codebase.

• Adds dart2wasm compatibility fix for browser tests
• Introduces comprehensive CI improvements including package health checks with pana
• Applies consistent code formatting across multiple files

Reviewed Changes

Copilot reviewed 11 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
.github/workflows/dart.yml	Adds package health job with pana, splits Chrome tests to test both dart2js and dart2wasm compilers, adds SDK version matrix to test job, and improves job naming
CHANGELOG.md	Adds entry for version 2.3.1
pubspec.yaml	Bumps version to 2.3.1
test/platform_test.dart	Adds dart:js_interop import and .toDart conversion for dart2wasm compatibility
dart_test.yaml	Removes node platform and ipv6 tags configuration
lib/io.dart	Adds @nodoc documentation annotation
lib/src/*.dart	Applies consistent code formatting and alignment across multiple source files
test/http_client_test.dart	Applies consistent code formatting to test functions and type definitions

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.