Add friendly message for when getTsConfig fails

When tsconfig.json is missing, the following errors is thrown:

```
⋯ Compiling TypeScript...
node:internal/process/esm_loader:34
internalBinding('errors').triggerUncaughtException(
^
TypeError [Error]: Cannot read properties of null (reading 'path')
at load (file:///.../node_modules/@ganesha/esbuild/loader.mjs:56:54)
at async nextLoad (node:internal/modules/esm/hooks:750:22)
at async Hooks.load (node:internal/modules/esm/hooks:383:20)
at async MessagePort.handleMessage (node:internal/modules/esm/worker:199:18)
```

Either:
* Tell the user to create a tsconfig
* Ignore the error and compile with default settings