feat(browse): sort dropdown in the tree toolbar

The tree's underlying setSort API was carried forward from the old
table-with-clickable-headers UI but had no widget driving it after
the layout reshape. Adds an explicit dropdown in the toolbar:

  Sort: [Name (A→Z)         ▾]
        [Name (Z→A)            ]
        [Modified (new→old)    ]
        [Modified (old→new)    ]
        [Size (large→small)    ]
        [Size (small→large)    ]
        [Type (A→Z)            ]

Implementation:
- new tree.setSortExplicit(key, dir) — sets both axes in one call
  (the existing tree.setSort toggles direction on repeat-clicks,
  which is the right semantics for column-header clicks but wrong
  for an explicit dropdown).
- events.js parses the dropdown value as "<key>:<asc|desc>" and
  calls setSortExplicit. The dropdown is initialised to reflect
  the current sort state on mount.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

browse/css/tree.css

@@ -476,3 +476,33 @@ html, body {
 .toc-level-4 a { padding-left: 2.7rem;  color: var(--text-muted); }
 .toc-level-5 a { padding-left: 3.35rem; color: var(--text-muted); font-size: 0.8rem; }
 .toc-level-6 a { padding-left: 4rem;    color: var(--text-muted); font-size: 0.8rem; }
+
+/* ── Sort control ────────────────────────────────────────────────────────── */
+.sort-control {
+    display: inline-flex;
+    align-items: center;
+    gap: 0.35rem;
+    font-size: 0.8rem;
+    color: var(--text-muted);
+    white-space: nowrap;
+}
+
+.sort-control__label {
+    user-select: none;
+}
+
+.sort-control__select {
+    font-family: var(--font);
+    font-size: 0.8rem;
+    padding: 0.2rem 0.4rem;
+    border: 1px solid var(--border);
+    border-radius: var(--radius);
+    background: var(--bg);
+    color: var(--text);
+    cursor: pointer;
+}
+
+.sort-control__select:focus {
+    outline: 2px solid var(--primary);
+    outline-offset: -1px;
+}

browse/js/events.js

@@ -122,6 +122,20 @@
         var refresh = document.getElementById('refreshHeaderBtn');
         if (refresh) refresh.addEventListener('click', refreshListing);
 
+        // Sort dropdown — change → tree re-renders with the new sort.
+        // Format of option value: "<key>:<asc|desc>". Defaults match
+        // state.sort initial values (name:asc).
+        var sortSel = document.getElementById('sortBy');
+        if (sortSel) {
+            sortSel.value = state.sort.key + ':' + (state.sort.dir > 0 ? 'asc' : 'desc');
+            sortSel.addEventListener('change', function () {
+                var parts = sortSel.value.split(':');
+                var key = parts[0];
+                var dir = parts[1] === 'desc' ? -1 : 1;
+                tree.setSortExplicit(key, dir);
+            });
+        }
+
         // View-mode toggle (Browse vs Grid)
         var btnBrowse = document.getElementById('viewModeBrowse');
         var btnGrid = document.getElementById('viewModeGrid');

browse/js/tree.js

@@ -513,6 +513,13 @@
             }
             render();
         },
+        // Set both key and direction explicitly. dir: 1 (asc) or -1 (desc).
+        // Used by the toolbar's sort dropdown.
+        setSortExplicit: function (key, dir) {
+            state.sort.key = key;
+            state.sort.dir = (dir === -1 ? -1 : 1);
+            render();
+        },
         pathFor: pathFor
     };
 })();

browse/template.html

@@ -59,6 +59,18 @@
                 </div>
                 <nav class="breadcrumbs" id="breadcrumbs" aria-label="Path"></nav>
                 <span class="toolbar__count" id="entryCount"></span>
+                <label class="sort-control" for="sortBy" title="Sort tree entries">
+                    <span class="sort-control__label">Sort:</span>
+                    <select id="sortBy" class="sort-control__select" aria-label="Sort tree entries">
+                        <option value="name:asc">Name (A→Z)</option>
+                        <option value="name:desc">Name (Z→A)</option>
+                        <option value="date:desc">Modified (new→old)</option>
+                        <option value="date:asc">Modified (old→new)</option>
+                        <option value="size:desc">Size (large→small)</option>
+                        <option value="size:asc">Size (small→large)</option>
+                        <option value="ext:asc">Type (A→Z)</option>
+                    </select>
+                </label>
             </div>
 
             <!-- Browse mode (default): two-pane tree + preview -->

zddc/internal/handler/tables.html

@@ -53,9 +53,9 @@
 /* The [data-theme="light"] selector locks light mode regardless of OS pref.   */
 @media (prefers-color-scheme: dark) {
     :root:not([data-theme="light"]) {
-        --primary:        #4a90c4;
-        --primary-hover:  #5ba3d9;
-        --primary-active: #6ab5e8;
+        --primary:        #5fa8e0;
+        --primary-hover:  #74b6e6;
+        --primary-active: #88c4ec;
         --primary-light:  #1a3550;
 
         --bg:           #1e1e1e;
@@ -74,9 +74,9 @@
 
 /* Manual dark override — wins over media query */
 [data-theme="dark"] {
-    --primary:        #4a90c4;
-    --primary-hover:  #5ba3d9;
-    --primary-active: #6ab5e8;
+    --primary:        #5fa8e0;
+    --primary-hover:  #74b6e6;
+    --primary-active: #88c4ec;
     --primary-light:  #1a3550;
 
     --bg:           #1e1e1e;
@@ -1155,7 +1155,7 @@ body.help-open .app-header {
             </svg>
             <div class="header-title-group">
                 <span class="app-header__title" id="table-title">ZDDC Table</span>
-                <span class="build-timestamp"><span style="color:red;font-weight:bold">v0.0.17-beta · 2026-05-11 · brass-dolphin-ivory</span></span>
+                <span class="build-timestamp"><span style="color:red;font-weight:bold">v0.0.17-alpha · 2026-05-11 00:21:36 · 89d96b7-dirty</span></span>
             </div>
         </div>
         <div class="header-right">