Implement Unit Testing for vitepress-plugin-moss

[CoderOMaster]

Request

Implement comprehensive unit tests for the vitepress-plugin-moss package to ensure reliability and maintainability.

Details

• Write unit tests covering the core features and modules of vitepress-plugin-moss.
• Utilize a suitable testing framework (e.g., Jest, Vitest).
• Ensure CI pipeline runs these tests.
• Provide documentation/examples for how to execute unit tests locally.

Acceptance Criteria

• All main modules in vitepress-plugin-moss are covered by meaningful unit tests.
• Clear instructions are provided for running the tests.
• Tests pass in the CI pipeline and report accurate results.

[PredictiveManish]

@CoderOMaster Also assign this, will make a PR soon, have gone halfway for the solution will submit once the work is done.