Show news header images at natural aspect ratio

The news article header forced every image into a fixed 240px-tall box with
object-fit: cover, which cropped the top and bottom of wide banners (and the
sides on narrow screens). The NeuroDataReHack 2026 banner is 3:1 and was
visibly clipped. Let the header image size to its natural aspect ratio so the
full banner is shown. All current news header images are landscape, so none
render unusually tall.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VhJgo7TdFYpPiuBehNr9im

Author: bendichter

layouts/news/single.html

@@ -32,7 +32,7 @@ <h3 class="inter-700 dark-900 text-48-responsive">{{ .Title | markdownify }}</h3
             <div class="col-lg-9">
                 <div>
                     <img src="{{ .Params.image }}" alt="" class="rounded-top-3"
-                        style="width: 100% !important; height: 240px !important; object-fit: cover !important;">
+                        style="width: 100% !important; height: auto !important;">
                 </div>
                 <div class="mt-4 bg-white px-5 py-2">
                     <div class="d-flex flex-column flex-sm-row gap-3">