Add Jest for unit testing (incomplete)

package.json

@@ -32,11 +32,13 @@
 		"@tailwindcss/forms": "^0.5.10",
 		"@tailwindcss/vite": "^4.1.14",
 		"@types/node": "^24",
+		"axios-mock-adapter": "^2.1.0",
 		"eslint": "^9.38.0",
 		"eslint-config-prettier": "^10.1.8",
 		"eslint-plugin-storybook": "^10.0.5",
 		"eslint-plugin-svelte": "^3.12.4",
 		"globals": "^16.4.0",
+		"jest": "^30.2.0",
 		"prettier": "^3.6.2",
 		"prettier-plugin-svelte": "^3.4.0",
 		"prettier-plugin-tailwindcss": "^0.7.1",