Rollup merge of #84460 - jyn514:doctree-is-crate, r=camelid

rustdoc: Remove unnecessary `is_crate` field from doctree::Module and clean::Module

It can be calculated on-demand even without a TyCtxt.

This also changed `json::conversions::from_item_kind` to take a whole item, which avoids
having to add more and more parameters.

Helps with https://github.com/rust-lang/rust/issues/76382.

r? ```@camelid```

src/librustdoc/html/render/print_item.rs

@@ -28,8 +28,8 @@ pub(super) fn print_item(cx: &Context<'_>, item: &clean::Item, buf: &mut Buffer)
     // Write the breadcrumb trail header for the top
     buf.write_str("<h1 class=\"fqn\"><span class=\"in-band\">");
     let name = match *item.kind {
-        clean::ModuleItem(ref m) => {
-            if m.is_crate {
+        clean::ModuleItem(_) => {
+            if item.is_crate() {
                 "Crate "
             } else {
                 "Module "