Microbundle to tsdown migration

[abetwothree]

This PR implements tsdown to address the vulnerability warnings associated with microbundler.

Functionally, it is the same as microbundler in how it bundles the files.

Long term, it will also allow for the current vanilla JS source files to be TypeScript and have tsdown convert to vanilla JS and generate .d.ts files automatically. That would remove the need for this command to exist ziggy:generate --types as types would be picked up automatically.

Thank you for your consideration 😄

[Copilot]

Pull request overview

Note

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This PR migrates the project’s bundling workflow from microbundle to tsdown, updates package entrypoints accordingly, and refreshes the generated dist/ outputs.

Changes:

• Add tsdown build configurations for ESM + UMD builds and a separate npm-focused ESM build.
• Update package.json scripts/entrypoints to use tsdown and remove microbundle.
• Update TypeScript compiler settings and regenerate dist/ artifacts.

Reviewed changes

Copilot reviewed 3 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tsdown.config.ts	Adds tsdown config for ESM + UMD builds, including dependency bundling rules.
tsdown.config.npm.ts	Adds a separate tsdown config for npm publishing (ESM only).
tsconfig.json	Enables skipLibCheck while keeping ESNext/Bundler settings.
package.json	Switches build scripts to tsdown, updates exports/module fields, and updates dev dependencies.
dist/route.umd.js	Updates the generated UMD bundle output.
dist/index.js	Updates the generated ESM bundle output.
dist/index.esm.js	Removes the previously generated ESM build file.

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[bakerkretzmar]

Thanks! Why was exports.import added in package.json, what does that do exactly?

I removed a bunch of options that were set to their default values, and added back a shim index.esm.js in case people are importing that.

Going to continue testing.

[abetwothree]

@bakerkretzmar exports.import is for ESM support. exports.require is for common js support.

See the section about "Conditional exports" in the link below
https://nodejs.org/api/packages.html