replace ava with vitest

Description

This issue does not include a description.

Contributor guide

Tech stack

typescriptvitest

Domain

testing

Issue type

chore

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

2

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-3 hours

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

stale

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

clear

Prerequisites

TypeScript knowledgebasic testing knowledge

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

70

Research direction

Replace the test runner from ava to vitest. This involves updating the package.json to replace ava with vitest, creating or updating vitest configuration, and updating all test files to use vitest imports (e.g., `describe`, `it`, `expect`). Make sure all existing tests still pass after migration.