Add inline SVG logo to sidebar (nozzle + layers mark)

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

app/templates/base.html

@@ -37,7 +37,17 @@
   <nav id="sidebar" class="p-3 d-flex flex-column gap-3">
     <a href="/" class="brand text-decoration-none pb-3">
       <div class="d-flex align-items-center gap-2">
-        <i class="bi bi-printer-fill text-primary fs-5"></i>
+        <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="24" height="24" fill="#58a6ff">
+            <!-- extruder head -->
+            <rect x="7" y="1" width="10" height="5" rx="1.5"/>
+            <!-- nozzle taper -->
+            <path d="M8 6h8l-2.5 5.5h-3z"/>
+            <!-- filament bead -->
+            <circle cx="12" cy="13.5" r="1.25"/>
+            <!-- printed layers -->
+            <rect x="1.5" y="16.5" width="21" height="2.5" rx="1.25"/>
+            <rect x="1.5" y="21" width="21" height="2" rx="1" fill-opacity="0.55"/>
+          </svg>
         <div>
           <div class="text-white fw-semibold lh-sm">POPS</div>
           <div class="text-secondary lh-sm" style="font-size:.68rem;letter-spacing:.03em">PRINT FARM MANAGER</div>