Enhancement/esbuild mode

[goransle]

No description provided.

[Copilot]

Pull request overview

This PR adds esbuild compilation support as an alternative build mode for faster compilation of Highcharts source files. Users can opt into esbuild by adding ?esbuild to any request URL.

Changes:

• Adds new esbuild compilation pipeline that integrates with @highcharts/highcharts-utils
• Implements query parameter detection (?esbuild) to route requests to the esbuild compiler
• Adds comprehensive test coverage for the new esbuild functionality

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/test.js	Adds esbuild test file to the test suite
test/esbuild.js	New comprehensive test suite covering esbuild compilation functions and core module exports
static/index.html	Updates example URLs to demonstrate esbuild mode with ?esbuild query parameter
package.json	Adds required dependencies: esbuild, esbuild-plugin-replace-regex, semver, and highcharts-utils
app/handlers.js	Implements esbuild mode detection and adds serveEsbuildFile handler function
app/esbuild.js	New module providing esbuild compilation functionality with caching and error handling
README.md	Extensive documentation of esbuild mode including usage, benefits, and troubleshooting
Dockerfile	Minor comment correction removing outdated "(yarn)" reference

[Copilot]

The dependency references a GitHub branch (enhancement/refactor-compile-on-demand) rather than a stable release version. For production deployments, consider using a specific commit SHA, tag, or published npm version to ensure reproducible builds and avoid breaking changes from branch updates.

Suggested change

	"@highcharts/highcharts-utils": "github:highcharts/highcharts-utils#enhancement/refactor-compile-on-demand",
	"@highcharts/highcharts-utils": "^1.5.6",