Align build with react/solid/… instead of svelte | fix default error typing | add simple example | add mutation controller

[JulianCataldo]

Hi :) Thanks for chiming in making Lit compatible with React Query!

This fixes build, so the root nx command, build:all, can succeed.

[JulianCataldo]

Added a working "lit simple" example + fixed a typing mismatch. It looks like react-query is using Error | null instead of unknown.

[JulianCataldo]

Added a mutation observer controller, with correct typings (from react-query etc.)
Build is OK.
A very quick runtime test was done, at least onSuccess seems to work.

@customElement('child-element')
export class ChildElement extends LitElement {
  @state() todoId = 1

  private todoQuery = todoQueryController(this)

  private todoMutation = new MutationController(this, () => ({
    mutationFn: (newTodo: { id: string }) => {
      console.log('OK')

      return new Promise((r) => r({}))
    },
  }))

 render() {
    const { isPending, error, data, isFetching } = this.todoQuery.result

    if (error) return 'An error has occurred: ' + error.message

    return html`

        <button
          @click=${() => {
            this.todoMutation.result.mutate(
              { id: 'string' },
              {
                onSuccess: () => {
                  console.log('OK')
                  queryClient.invalidateQueries({ queryKey: ['todo'] })
                },
              },
            )
          }}
        >
          MUTATE
        </button>
`
//...

}