fix: update package.json to support Svelte legacy tooling

- REF https://kit.svelte.dev/docs/packaging#anatomy-of-a-package-json-svelte
- Downgrade to Svelte 3.59.2 because 4.0.0 exports the package using a type `SvelteComponent` which causes the types to break when used in Svelte 3.x — REF sveltejs/svelte#8512

Fixes #68

package.json

@@ -24,7 +24,7 @@
 		"!dist/**/*.spec.*"
 	],
 	"peerDependencies": {
-		"svelte": "^4.0.0"
+		"svelte": "^3.59.2"
 	},
 	"devDependencies": {
 		"@playwright/test": "^1.39.0",
@@ -49,6 +49,8 @@
 		"typescript": "^5.0.0",
 		"vite": "^4.4.2"
 	},
+	"svelte": "./dist/index.js",
+	"types": "./dist/index.d.ts",
 	"type": "module",
 	"description": "A form input that converts numbers to currencies as you type in localized formats",
 	"keywords": [