switch to a Document trait and introduce Script/Head/Style/Meta components (#2635)

* switch to a Document trait and introduce Script/Head/Style/Meta components

* Fix desktop title

* Insert special elements into the head during the inital SSR render

* Make all head component attributes optional

* hydrate head elements

* improve the server streaming head warning

* Document fullstack head hydration approach

* deduplicate head elements by href

* move Link into head::Link

* document head components

* add meta and title examples

* Fix a few doc examples

* fix formatting

* Add title to playwright tests

* serde is optional on web, but it is enabled by hydrate

* remove leftover console log

packages/fullstack/src/html_storage/mod.rs

@@ -32,7 +32,11 @@ impl SerializeContext {
 }
 
 pub(crate) fn use_serialize_context() -> SerializeContext {
-    use_hook(|| has_context().unwrap_or_else(|| provide_context(SerializeContext::default())))
+    use_hook(serialize_context)
+}
+
+pub(crate) fn serialize_context() -> SerializeContext {
+    has_context().unwrap_or_else(|| provide_context(SerializeContext::default()))
 }
 
 #[derive(serde::Serialize, serde::Deserialize, Default)]