Need an idiomatic way to insert HTML text

Currently, the variables and string constants are inserted using the `innerText` property. This causes HTML encoded elements like ` ` or `»` to show up as the code, and not as a space or » character.

There's a hacky way to make that happen using the `innerHTML` property, like this:
``

However, this is not in the documentation and is more of a workaround than a standard way of doing it.

It also does not offer a way to insert the HTML without adding another level to the DOM tree.

There should be a way to insert HTML from a variable or expression without adding an extra element.

For example something like this:
```
// this can be coming from an API call
let price= "$11.95$9.99"

No source file, test, or entry point is named. Start by locating the implementation of `innerText` insertion and the template syntax for expressions, then determine how a proposed HTML-insertion construct should handle nested content and untrusted API values; done means the documented syntax inserts the example markup without an extra wrapper.

Written by the indexing model from the issue text.