FilesBlock: move size under icon, drop redundant ext label

Icon already communicates file type. Size now sits below the icon
in a fixed-width left column. Ext text removed.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/components/blocks/FilesBlock.svelte

@@ -125,14 +125,16 @@
             target="_blank"
             rel="noopener noreferrer"
           >
-            <Icon icon={f.iconName} class="size-4 shrink-0 text-stein-500" aria-hidden="true" />
+            <span class="shrink-0 flex flex-col items-center w-8">
+              <Icon icon={f.iconName} class="size-4 text-stein-500" aria-hidden="true" />
+              {#if f.sizeLabel}
+                <span class="text-[.6rem] text-stein-400 tabular-nums leading-tight">{f.sizeLabel}</span>
+              {/if}
+            </span>
             <span class="flex-1 min-w-0 text-sm text-stein-900 group-hover:underline truncate">{f.label}</span>
             {#if f.description}
               <span class="hidden md:block text-xs text-stein-400 truncate max-w-48">{f.description}</span>
             {/if}
-            <span class="shrink-0 text-xs text-stein-400 tabular-nums">
-              {#if f.ext}<span class="uppercase">{f.ext}</span>{/if}{#if f.ext && f.sizeLabel} · {/if}{#if f.sizeLabel}{f.sizeLabel}{/if}
-            </span>
           </a>
         </li>
       {/each}