fix: handle SVG images in responsive image processing

SVG resources don't support .Width, .Height, or .Process in Hugo,
causing crashes in process_responsive_image.html and all callers
that pass SVGs without guards.

Add SVG checks to process_responsive_image.html, preact-wrapper.html,
resume-biography, resume-biography-3, authors/term, and
page_author_card.

Fixes #3305

modules/blox/layouts/_partials/functions/process_responsive_image.html

@@ -138,8 +138,7 @@ Returns: Map with processed images and srcset string
   {{- end -}}
   {{ end }}
 {{- else -}}
-  {{/* Handle unsupported formats (SVG, GIF) */}}
-  {{- $srcset_parts = $srcset_parts | append (printf "%s %dw" $image.RelPermalink $image.Width) -}}
+  {{/* Handle unsupported formats (SVG, GIF) - skip srcset as width/height are unavailable for SVGs */}}
   {{- $fallback_image = $image -}}
   {{- $processed_images = $processed_images | append $image -}}
 {{- end -}}