fix: related-content: Handle missing file context

This commit addresses an issue where `$page_context.File` could be nil, causing errors. It adds checks to ensure file context exists before accessing its properties.
Also the software tag comparison should not happen on pages where the slug is empty.
The thumbnail rendering was adjusted to only be rendered when an image is specified in the front matter.

Author: neural-loop

layouts/partials/shared/related-content.html

@@ -2,7 +2,10 @@
 {{ $related_items := slice }}
 
 {{ $current_type := $page_context.Type }}
-{{ $current_slug := path.Base $page_context.File.Dir }}
+{{ $current_slug := "" }}
+{{ if $page_context.File }}
+  {{ $current_slug = path.Base $page_context.File.Dir }}
+{{ end }}
 {{ $current_title := $page_context.Title }}
 
 
@@ -15,7 +18,7 @@
     {{ $tag_param_key = ".Params.software_tags" }}
 {{ end }}
 
-{{ if ne $tag_param_key "" }}
+{{ if and (ne $tag_param_key "") (ne $current_slug "") }}
     {{ $tagged_pages := where site.RegularPages $tag_param_key "intersect" (slice $current_slug) }}
     {{ range $tagged_pages }}
         {{ $related_items = $related_items | append . }}
@@ -31,14 +34,15 @@
         {{ $software_slugs_to_find := . }}
         {{ $all_software_pages := where site.RegularPages "Type" "neuromorphic-software" }}
         {{ range $software_page := $all_software_pages }}
-            {{ $software_slug := path.Base $software_page.File.Dir }}
-            {{ if in $software_slugs_to_find $software_slug }}
+            {{ $software_slug := "" }}
+            {{ if $software_page.File }}{{ $software_slug = path.Base $software_page.File.Dir }}{{ end }}
+            {{ if and (ne $software_slug "") (in $software_slugs_to_find $software_slug) }}
                 {{ $related_items = $related_items | append $software_page }}
             {{ end }}
         {{ end }}
     {{ end }}
 
-{{ else if eq $current_type "neuromorphic-software" }}
+{{ else if and (eq $current_type "neuromorphic-software") (ne $current_slug "") }}
     {{/* I am a software page. Find hardware that supports me. */}}
     {{ $hardware_pages := where site.RegularPages "Type" "neuromorphic-hardware" }}
     {{ range where $hardware_pages ".Params.software_tags" "intersect" (slice $current_slug) }}
@@ -47,7 +51,7 @@
 {{ end }}
 
 {{/* --- Finalize and Render --- */}}
-{{/* Deduplicate without uniqBy for older Hugo versions */}}
+{{/* Deduplicate */}}
 {{ $unique_related_items := slice }}
 {{ $seen_permalinks := slice }}
 {{ range $related_items }}
@@ -68,47 +72,31 @@ <h2 class="text-3xl font-bold mb-8">Related Content, Events & Resources</h2>
     <div class="timeline-item-content">
       <div class="flex flex-col md:flex-row items-start gap-5">
 
-        {{/* Thumbnail Column */}}
-        <div class="flex-shrink-0 w-full md:w-40 text-center">
-          <a href="{{ $item.RelPermalink }}">
-            {{ $image_param := $item.Params.image }}
-            {{ $img_path := "" }}
-            {{ $img_alt := $item.Title }}
-
-            {{ if $image_param }}
+        {{/* Thumbnail Column - Renders only if image is in front matter */}}
+        {{ with $item.Params.image }}
+          <div class="flex-shrink-0 w-full md:w-40 text-center">
+            <a href="{{ $item.RelPermalink }}">
+              {{ $image_param := . }}
+              {{ $img_path := "" }}
+              {{ $img_alt := $item.Title }}
+
               {{ $img_path_cleaned := strings.TrimPrefix "/" $image_param }}
               {{ $resource := "" }}
-              {{ with $item.Resources.GetMatch $image_param }}
-                {{ $resource = . }}
-              {{ else }}
-                {{ with resources.Get $img_path_cleaned }}
-                  {{ $resource = . }}
-                {{ end }}
-              {{ end }}
-
+              {{ with $item.Resources.GetMatch $image_param }}{{ $resource = . }}{{ end }}
+              {{ if not $resource }}{{ with resources.Get $img_path_cleaned }}{{ $resource = . }}{{ end }}{{ end }}
+              
               {{ if $resource }}
                 {{ $img_path = ($resource.Fill "160x90 Lanczos").RelPermalink }}
               {{ else if fileExists (printf "static/%s" $img_path_cleaned) }}
                 {{ $img_path = $image_param | relURL }}
               {{ end }}
-            {{ end }}
 
-            {{ if not $img_path }}
-              {{ with resources.Get "images/workshop-thumbnail-default.png" }}
-                {{ $img_path = (.Fill "160x90 Lanczos").RelPermalink }}
-                {{ $img_alt = "Default Open Neuromorphic Event Thumbnail" }}
+              {{ if $img_path }}
+                <img src="{{ $img_path }}" alt="{{ $img_alt }}" class="w-full h-auto rounded-md object-cover">
               {{ end }}
-            {{ end }}
-
-            {{ if $img_path }}
-              <img src="{{ $img_path }}" alt="{{ $img_alt }}" class="w-full h-auto rounded-md object-cover">
-            {{ else }}
-              <div class="w-full h-[90px] bg-gray-200 dark:bg-darkmode-theme-dark rounded-md flex items-center justify-center">
-                {{ partial "icon.html" (dict "style" "regular" "name" "images" "class" "text-4xl text-gray-400") }}
-              </div>
-            {{ end }}
-          </a>
-        </div>
+            </a>
+          </div>
+        {{ end }}
 
         {{/* Content Column */}}
         <div class="flex-grow">