chore(packages): add test coverage support to plugin sdk and shared package

shared/package.json

@@ -54,6 +54,7 @@
     "build:watch": "tsdown --watch --no-clean",
     "test": "vitest run",
     "test:watch": "vitest",
+    "test:coverage": "vitest run --coverage",
     "typecheck": "tsc --noEmit",
     "format": "prettier --write \"src/**/*.ts\"",
     "format:check": "prettier --check \"src/**/*.ts\"",
@@ -68,6 +69,7 @@
   "devDependencies": {
     "@eslint/js": "^10.0.1",
     "@trivago/prettier-plugin-sort-imports": "^6.0.2",
+    "@vitest/coverage-v8": "^4.1.9",
     "eslint": "^10.3.0",
     "eslint-config-flat-gitignore": "^2.3.0",
     "eslint-config-prettier": "^10.1.8",