feat: add sort/filter component for watchlist

- create reusable SortFilter templ component with sort options (date, title, score)
- integrate sort/filter into watchlist page with query params
- add sortEntries method to handle client-side sorting
- add CSS styling for sort filter controls
- pass sort params through status tab and view toggle links

static/css/style.css

@@ -857,6 +857,43 @@ a:visited {
   margin: 0;
 }
 
+/* Sort Filter */
+.sort-filter {
+  display: flex;
+  gap: 16px;
+  margin-bottom: 16px;
+  padding: 12px;
+  background: var(--surface);
+  border: 1px solid var(--border);
+}
+
+.sort-filter-group {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.sort-filter-group label {
+  font-size: 12px;
+  color: var(--text-muted);
+  font-weight: 500;
+}
+
+.sort-filter-select {
+  background: var(--surface);
+  border: 1px solid var(--border);
+  color: var(--text);
+  padding: 6px 8px;
+  font-size: 12px;
+  font-family: inherit;
+  cursor: pointer;
+}
+
+.sort-filter-select:focus {
+  outline: none;
+  border-color: var(--link);
+}
+
 /* Responsive */
 @media (max-width: 900px) {
   .anime-page {