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Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
Provide a description in this PR that addresseswhat the PR is solving, or reference the issue that it solves (e.g.fixes #123).
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⚠️ Slowing down new functions

Warning:Slowing down new functions
As the VueUse audience continues to grow, we have been inundated with an overwhelming number of feature requests and pull requests. As a result, maintaining the project has become increasingly challenging and has stretched our capacity to its limits. As such, in the near future, we may need to slow down our acceptance of new features and prioritize the stability and quality of existing functions.Please note that new features for VueUse may not be accepted at this time. If you have any new ideas, we suggest that you first incorporate them into your own codebase, iterate on them to suit your needs, and assess their generalizability. If you strongly believe that your ideas are beneficial to the community, you may submit a pull request along with your use cases, and we would be happy to review and discuss them. Thank you for your understanding.

Description

This PR adds comprehensive test coverage for theuseStorageAsync composable, which was missing test cases.

What this PR solves:

Adds 28 test cases covering all functionality ofuseStorageAsync
Ensures proper testing of async storage operations
Improves code quality and maintainability through better test coverage

Test coverage includes:

Basic data types (string, number, boolean, null, undefined)
Complex data structures (objects, arrays, Map, Set, Date)
All configuration options (eventFilter, mergeDefaults, writeDefaults, shallow, flush)
Error handling scenarios (read errors, write errors, serialization errors)
Async operations and storage synchronization
Edge cases and storage events

Additional context

This PR only adds tests without modifying the existinguseStorageAsync implementation
All tests are designed to work with the current async storage interface
The test file follows the project's testing conventions and uses the same testing utilities
No breaking changes or new dependencies are introduced