Move the document trait into a separate crate (#3035)

* add a default head method through eval
* remove the old document trait
* implement document for each platform
* pull out document into a dedicated crate to cut down on shared dependencies
---------

Co-authored-by: Jonathan Kelley <jkelleyrtp@gmail.com>

packages/cli/src/builder/prepare_html.rs

@@ -156,7 +156,7 @@ impl BuildRequest {
                 };
                 match variant {
                     ResourceType::Style => format!(
-                        "    head::Link {{ rel: \"stylesheet\", href: asset!(css(\"{}\")) }}",
+                        "    document::Link {{ rel: \"stylesheet\", href: asset!(css(\"{}\")) }}",
                         path.display()
                     ),
                     ResourceType::Script => {