implemented stock display from location tree to property list

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

frontend/src/routes/stock/ItemProps.svelte

@@ -1,5 +1,22 @@
-<ul>
-    <li>Prop 1</li>
-    <li>Prop 2</li>
-    <li>Prop 3</li>
-</ul>
+<script>
+    let { item } = $props();
+</script>
+
+{#if item}
+<h3>{item.name}</h3>
+<table>
+    <tbody>
+        {#each item.properties as prop}
+        <tr>
+            <td>
+                {prop.name}
+            </td>
+            <td>
+                {prop.value}
+                {prop.unit}
+            </td>
+        </tr>
+        {/each}
+    </tbody>
+</table>
+{/if}