feat: support hiding the main sidebar in desktop site (#778)

* feat: Remove the main sidebar entirely to free up more space for the main content of the page

* fix: ensure that the footer switches are still visible when the main sidebar has been disabled

* refactor: Repurpose Params.sidebar.hide to disable the main sidebar and disable the placeholder rather than adding a new front matter parameter

* fix: change wording from "disable" to "hide" in the documentation for hiding the sidebar

* fix: using incorrect hidden class in sidebar.html broke mobile navigation. Fixed this

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Co-authored-by: Xin <5097752+imfing@users.noreply.github.com>

layouts/_partials/sidebar.html

@@ -3,17 +3,22 @@
 {{- $disableSidebar := .disableSidebar | default false -}}
 {{- $displayPlaceholder := .displayPlaceholder | default false -}}
 
-{{- $sidebarClass := cond $disableSidebar (cond $displayPlaceholder "hx:md:hidden hx:xl:block" "hx:md:hidden") "hx:md:sticky" -}}
-
 {{- $navRoot := cond (eq site.Home.Type "docs") site.Home $context.FirstSection -}}
 {{- $pageURL := $context.RelPermalink -}}
 
-{{/* EXPERIMENTAL */}}
 {{- if .context.Params.sidebar.hide -}}
   {{- $disableSidebar = true -}}
-  {{- $displayPlaceholder = true -}}
+  {{- $displayPlaceholder = false -}}
 {{- end -}}
 
+{{- $sidebarClass := "hx:md:sticky" -}}
+{{- if $disableSidebar -}}
+  {{- if $displayPlaceholder -}}
+    {{- $sidebarClass = "hx:md:hidden hx:xl:block" -}}
+  {{- else -}}
+    {{- $sidebarClass = "hx:md:hidden" -}}
+  {{- end -}}
+{{- end -}}
 
 <aside class="hextra-sidebar-container hx:flex hx:flex-col hx:print:hidden hx:md:top-16 hx:md:shrink-0 hx:md:w-64 hx:md:self-start hx:max-md:[transform:translate3d(0,-100%,0)] {{ $sidebarClass }}">
   <!-- Search bar on small screen -->