Add TypeScript declaration files for proper TypeScript support

[christoph2806]

Issue Description

The @etherisc/ui-kit package (v0.2.1) is missing TypeScript declaration files (.d.ts), causing TypeScript compilation errors in projects that use the package.

Current Behavior

When importing components from @etherisc/ui-kit in a TypeScript project:

import { Select, Button, DataTable } from '@etherisc/ui-kit';

TypeScript throws errors:

error TS7016: Could not find a declaration file for module '@etherisc/ui-kit'. 
'/workspace/node_modules/@etherisc/ui-kit/dist/ui-kit.js' implicitly has an 'any' type.
Try `npm i --save-dev @types/etherisc__ui-kit` if it exists or add a new declaration (.d.ts) file containing `declare module '@etherisc/ui-kit';`

Expected Behavior

The package should include TypeScript declaration files so that:

1. TypeScript projects can use the package without compilation errors
2. Developers get proper type checking and IntelliSense support
3. Component props are properly typed for better development experience

Environment

• Package version: @etherisc/ui-kit@0.2.1
• TypeScript version: Latest
• Build tool: Vite with TypeScript

Suggested Solution

1. Add TypeScript declarations to the build process

   • Include .d.ts files in the dist/ directory
   • Update package.json to reference the types: "types": "./dist/index.d.ts"

2. Ensure proper exports

   • All components (Button, Select, DataTable, etc.) should have proper type exports
   • Hook functions (useToast, useToastContext) should have typed return values

3. Example package.json structure:

   {
     "name": "@etherisc/ui-kit",
     "version": "0.2.1",
     "main": "./dist/ui-kit.umd.cjs",
     "module": "./dist/ui-kit.js",
     "types": "./dist/index.d.ts",
     "exports": {
       ".": {
         "types": "./dist/index.d.ts",
         "import": "./dist/ui-kit.js",
         "require": "./dist/ui-kit.umd.cjs"
       }
     }
   }

Additional Context

This issue prevents proper TypeScript integration and forces developers to either:

• Use // @ts-ignore everywhere
• Create custom declaration files that may become outdated
• Disable TypeScript strict mode

Adding proper TypeScript support would greatly improve the developer experience and make the package more suitable for enterprise TypeScript projects.

Related

This follows up on issue #39 regarding the Select component export, which was resolved. Now we need the TypeScript declarations to complete the proper package support.

[christoph2806]

closed with PR #42