Errors due to raw TypeScript distribution, instead of a .js + .d.ts combo

[platosha]

This package distributes raw TypeScript and lacks JS entrypoints. This has several disadvantages over shipping .js + .d.ts:

• Requires TypeScript and compiling from the user.
• Affected by the user's TypeScript compiler settings. The result is prone to breaking. Errors like this one might occur due to misaligned TypeScript settings:

  ERROR(TypeScript)  An import path can only end with a '.ts' extension when 'allowImportingTsExtensions' is enabled.
  FILE  node_modules/@vaadin-component-factory/vcf-nav/vcf-nav.ts:1:8
   > 1 | import './src/vcf-nav.ts';
       |        ^^^^^^^^^^^^^^^^^^
     2 | import './src/vcf-nav-item.ts';
     3 |
  

• Missing TypeScript compilation as a validation step when publishing the package. The source here might not be a valid TypeScript after all, and we only know it when the usage breaks elsewhere.

Let us introduce its own tsconfig.json in this repo, add compilation as a publishing step, and distribute compiled .js + .d.ts.

[ugur-vaadin]

This change is included in the initial version of the official component.