* move `is_readonly` into the common `Binding` AST class
* prevents the following bindings from being emitted into the SSR code:
* `bind:clientWidth`
* `bind:clientHeight`
* `bind:offsetWidth`
* `bind:offsetHeight`
* `bind:duration`
* `bind:buffered`
* `bind:seekable`
* `bind:played`
* `bind:value` (only for `input` with `type=file`)