fix: add Vitest coverage config for issue #396

[ryzen-xp]

Summary

Added coverage reporting support to Vitest to improve backend reliability tracking and make test coverage transparent.

• Configured vitest.config.ts to enable coverage with v8 provider.
• Set output reporter to html and text-summary.
• Set coverage output directory to coverage.
• Excluded structural/type-only files and test files from coverage counting.
• Added npm script test:coverage to run vitest run --coverage.
• Added dependency @vitest/coverage-v8 to devDependencies.

Type of Change

• Feature
• Bug Fix
• Refactoring
• Documentation
• Tests
• Infrastructure / CI

Linked Issues

• Close Add coverage reporting to Vitest config #396

Key Changes

• vitest.config.ts
  • test.coverage section:
    • provider: "v8"
    • reporter: ["html", "text-summary"]
    • reportsDirectory: "coverage"
    • all: true, clean: true
    • exclude for index files, *.d.ts, *.type.ts, *.types.ts, and tests.
• package.json
  • new script:
    • "test:coverage": "vitest run --coverage"
• Added @vitest/coverage-v8 to devDependencies.
• Verified command execution: pnpm test:coverage runs tests and produces HTML report under /coverage/index.html.

Checklist

• I have performed a self-review of my code.
• I have commented my code, particularly in hard-to-understand areas.
• My changes generate no new linting/type-checking warnings.
• I have added tests that prove my fix is effective or that my feature works.
• I have updated the documentation accordingly.

Screenshots / Recordings

• Generated coverage/index.html from pnpm test:coverage (manual local verification).
• No screenshot included in this text response.

[ryzen-xp]

hello @codeZe-us , Please Review This PR .

Thank U !!