Release v0.2.2 - Display file checksums in UI

Features:
- Add SHA256 column to admin product versions table
- Display file hash in customer account downloads section
- Style checksum file upload field consistently with package upload

Changes:
- Admin versions table shows truncated hash with full hash on hover
- Customer downloads show hash with shield icon indicator
- Updated German translations

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

assets/css/frontend.css

@@ -247,6 +247,30 @@
     margin-left: auto;
 }
 
+.download-hash {
+    display: inline-flex;
+    align-items: center;
+    gap: 0.25em;
+    font-size: 0.8em;
+    color: #666;
+}
+
+.download-hash .dashicons {
+    font-size: 14px;
+    width: 14px;
+    height: 14px;
+    color: #28a745;
+}
+
+.download-hash code {
+    font-family: 'SF Mono', Monaco, Consolas, monospace;
+    background: #f5f5f5;
+    padding: 0.2em 0.4em;
+    border-radius: 3px;
+    font-size: 0.9em;
+    color: #666;
+}
+
 /* Domain Field */
 #licensed-product-domain-field {
     margin-top: 2em;