Simplify social images and add ability to set per-page images

- Removes the homepage summary layout in favor of the larger image card (makes it more consistent with other pages)
- Reuses new thumbnails for Webpack, Parcel, and Vite guides to add their new social images

site/content/docs/5.2/getting-started/parcel.md

@@ -4,6 +4,7 @@ title: "Bootstrap & Parcel"
 description: The official guide for how to include and bundle Bootstrap's CSS and JavaScript in your project using Parcel.
 group: getting-started
 toc: true
+thumbnail: guides/bootstrap-parcel@2x.png
 ---
 
 <img class="mb-4 img-fluid rounded-3" srcset="/docs/{{< param docs_version >}}/assets/img/guides/bootstrap-parcel.png, /docs/{{< param docs_version >}}/assets/img/guides/bootstrap-parcel@2x.png 2x" src="/docs/{{< param docs_version >}}/assets/img/guides/bootstrap-parcel.png" width="2000" height="1000" alt="">

site/content/docs/5.2/getting-started/vite.md

@@ -4,6 +4,7 @@ title: "Bootstrap & Vite"
 description: The official guide for how to include and bundle Bootstrap's CSS and JavaScript in your project using Vite.
 group: getting-started
 toc: true
+thumbnail: guides/bootstrap-vite@2x.png
 ---
 
 <img class="mb-4 img-fluid rounded-3" srcset="/docs/{{< param docs_version >}}/assets/img/guides/bootstrap-vite.png, /docs/{{< param docs_version >}}/assets/img/guides/bootstrap-vite@2x.png 2x" src="/docs/{{< param docs_version >}}/assets/img/guides/bootstrap-vite.png" width="2000" height="1000" alt="">

site/content/docs/5.2/getting-started/webpack.md

@@ -4,6 +4,7 @@ title: "Bootstrap & Webpack"
 description: The official guide for how to include and bundle Bootstrap's CSS and JavaScript in your project using Webpack.
 group: getting-started
 toc: true
+thumbnail: guides/bootstrap-webpack@2x.png
 ---
 
 <img class="mb-4 img-fluid rounded-3" srcset="/docs/{{< param docs_version >}}/assets/img/guides/bootstrap-webpack.png, /docs/{{< param docs_version >}}/assets/img/guides/bootstrap-webpack@2x.png 2x" src="/docs/{{< param docs_version >}}/assets/img/guides/bootstrap-webpack.png" width="2000" height="1000" alt="">

site/layouts/partials/social.html

@@ -1,17 +1,25 @@
-{{ "<!-- Twitter -->" | safeHTML }}
-<meta name="twitter:card" content="{{ if .IsHome }}summary_large_image{{ else }}summary{{ end }}">
+<meta name="twitter:card" content="summary_large_image">
 <meta name="twitter:site" content="@{{ .Site.Params.twitter }}">
 <meta name="twitter:creator" content="@{{ .Site.Params.twitter }}">
 <meta name="twitter:title" content="{{ .Title | markdownify }}">
 <meta name="twitter:description" content="{{ .Page.Params.description | default .Site.Params.description | markdownify }}">
-<meta name="twitter:image" content="{{ if .IsHome }}{{ .Site.Params.social_logo_path | absURL }}{{ else }}{{ .Site.Params.social_image_path | absURL }}{{ end }}">
 
-{{ "<!-- Facebook -->" | safeHTML }}
+{{ if .Page.Params.thumbnail }}
+<meta name="twitter:image" content="/docs/{{ .Site.Params.docs_version }}/assets/img/{{ .Page.Params.thumbnail }}">
+{{ else }}
+<meta name="twitter:image" content="{{ .Site.Params.social_image_path | absURL }}">
+{{ end }}
+
 <meta property="og:url" content="{{ .Permalink }}">
 <meta property="og:title" content="{{ .Title | markdownify }}">
 <meta property="og:description" content="{{ .Page.Params.description | default .Site.Params.description | markdownify }}">
 <meta property="og:type" content="{{ if .IsPage }}article{{ else }}website{{ end }}">
-<meta property="og:image" content="{{ .Site.Params.social_image_path | absURL }}">
 <meta property="og:image:type" content="image/png">
 <meta property="og:image:width" content="1000">
 <meta property="og:image:height" content="500">
+
+{{ if .Page.Params.thumbnail }}
+<meta property="og:image" content="/docs/{{ .Site.Params.docs_version }}/assets/img/{{ .Page.Params.thumbnail }}">
+{{ else }}
+<meta property="og:image" content="{{ .Site.Params.social_image_path | absURL }}">
+{{ end }}