Add fallback to default language for code_sample shortcode

This imporves internationalization support by falling back to the default
language's examples when a translation doesn't exist, prevention build errors
for missing localized code samples.

- Refactor code_sample.html to handle missing files more gracefully
- Move filename generation to scratch variable for reusability
- Add fallback logic to try default language when file not found in current language
- Reorganize source lookup flow with proper conditional blocks
- Maintain existing ghlink generation with updated filename variable

Author: Eundms

layouts/shortcodes/code_sample.html

@@ -3,20 +3,26 @@
 {{ $codelang := .Get "language" | default (path.Ext $file | strings.TrimPrefix ".") }}
 {{ $fileDir := path.Split $file }}
 {{ $bundlePath := path.Join .Page.File.Dir $fileDir.Dir }}
-{{ $filename := printf "/content/%s/examples/%s" .Page.Lang $file | safeURL }}
-{{ $ghlink := printf "https://%s/%s%s" site.Params.githubwebsiteraw (default "main" site.Params.docsbranch) $filename | safeURL }}
+{{ $.Scratch.Set "filename" (printf "/content/%s/examples/%s" .Page.Lang $file) }}
 {{/* First assume this is a bundle and the file is inside it. */}}
-{{ $resource := $p.Resources.GetMatch (printf "%s*" $file ) }}
-{{ with $resource }}
+{{ with $p.Resources.GetMatch (printf "%s*" $file) }}
 {{ $.Scratch.Set "content" .Content }}
-{{ else }}
+{{ end }}
 {{/* Read the file relative to the content root. */}}
-{{ $resource := readFile $filename}}
-{{ with $resource }}{{ $.Scratch.Set "content" . }}{{ end }}
+{{ with readFile ($.Scratch.Get "filename")}}
+{{ $.Scratch.Set "content" . }}
+{{ end }}
+{{/* If not found, try the default language */}}
+{{ $defaultLang := (index (sort site.Languages "Weight") 0).Lang }}
+{{ with readFile (printf "/content/%s/examples/%s" $defaultLang $file) }}
+{{ $.Scratch.Set "content" . }}
+{{ $.Scratch.Set "filename" (printf "/content/%s/examples/%s" $defaultLang $file) }}
 {{ end }}
 {{ if not ($.Scratch.Get "content") }}
 {{ errorf "[%s] %q not found in %q" site.Language.Lang $fileDir.File $bundlePath }}
 {{ end }}
+{{ $filename := printf ($.Scratch.Get "filename") | safeURL }}
+{{ $ghlink := printf "https://%s/%s%s" site.Params.githubwebsiteraw (default "main" site.Params.docsbranch) $filename | safeURL }}
 {{ with $.Scratch.Get "content" }}
 <div class="highlight code-sample">
     <div class="copy-code-icon">