feat(site-builder): copy/paste style and saved style presets

Refs #48

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

craft/src/styles/editor.css

@@ -2731,3 +2731,60 @@ body {
   color: var(--color-text);
   cursor: pointer;
 }
+
+/* #48 presets */
+.wsb-presets-popover {
+  min-width: 200px;
+  max-width: 260px;
+  padding: 8px;
+  display: flex;
+  flex-direction: column;
+  gap: 6px;
+  font-size: 12px;
+  color: var(--color-text);
+  background: var(--color-bg-elevated);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-md);
+  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.5);
+}
+.wsb-presets-label { font-size: 11px; color: var(--color-text-dim); }
+.wsb-presets-input {
+  padding: 5px 8px;
+  font-size: 12px;
+  color: var(--color-text);
+  background: var(--color-bg);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm, 4px);
+}
+.wsb-presets-btn {
+  padding: 5px 8px;
+  font-size: 12px;
+  color: var(--color-text);
+  background: var(--color-bg-hover);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm, 4px);
+  cursor: pointer;
+}
+.wsb-presets-btn:disabled { opacity: 0.5; cursor: default; }
+.wsb-presets-empty { padding: 4px; color: var(--color-text-dim); }
+.wsb-presets-list { margin: 0; padding: 0; list-style: none; }
+.wsb-presets-row { display: flex; align-items: center; justify-content: space-between; gap: 4px; }
+.wsb-presets-apply {
+  flex: 1;
+  padding: 6px 8px;
+  text-align: left;
+  font-size: 12px;
+  color: var(--color-text);
+  background: transparent;
+  border: 0;
+  border-radius: var(--radius-sm, 4px);
+  cursor: pointer;
+}
+.wsb-presets-apply:hover { background: var(--color-bg-hover); }
+.wsb-presets-delete {
+  padding: 4px 6px;
+  color: var(--color-danger);
+  background: transparent;
+  border: 0;
+  cursor: pointer;
+}