refactor: improve compatibility with node test runner

[Uzlopak]

This is making tspl closer to node test runner.
Also types are generated from jsdoc.

Adds t.plan method to set the plan.

This will help in the long run, to remove tspl in the future, when people drop node 18 and node 20 support.

Tested directly against undici repo and it worked accordingly.

[Copilot]

Pull Request Overview

This PR refactors tspl to improve compatibility with the Node.js test runner by adding new features and generating types from JSDoc comments. The changes include adding a t.plan() method, providing a done callback option, and exposing assertion methods through both direct properties and a dedicated t.assert object.

• Adds t.plan() method to dynamically set the expected number of assertions
• Introduces done callback option for handling test completion with optional error handling
• Exposes assertion methods through t.assert property for better compatibility with Node.js test patterns

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tspl.js	Core refactoring with JSDoc types, plan method, done callback, and assert property
tspl.test-d.ts	Type definition tests for the new assert property
tsconfig.types.json	TypeScript configuration for generating types from JSDoc
test.js	Comprehensive test coverage for new features including done callback and assert property
package.json	Build scripts for type generation and TypeScript dependency

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[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 6 changed files in this pull request and generated 1 comment.

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[mcollina]

Can you update the readme?

[Uzlopak]

@mcollina

t.plan is now working like the one from node test runner.

[Copilot]

Pull Request Overview

Copilot reviewed 6 out of 7 changed files in this pull request and generated 3 comments.

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[Uzlopak]

modified the readme

@mcollina
PTAL