fix docs table of contents scrolling

public/js/admin-docs.js

@@ -107,6 +107,43 @@
     }).join('');
   }
 
+  // marked no longer guarantees heading ids across versions, and the docs
+  // reader is an internal scroll container. Add stable GitHub-style ids and
+  // handle same-page #toc links by scrolling the reader, not the window.
+  function slugHeading(text) {
+    return String(text || '')
+      .trim()
+      .toLowerCase()
+      .replace(/\s/g, '-')
+      .replace(/[^a-z0-9_-]/g, '');
+  }
+
+  function prepareDocAnchors(body) {
+    if (!body) return;
+    var seen = {};
+    body.querySelectorAll('h1,h2,h3,h4,h5,h6').forEach(function (h) {
+      var base = h.id || slugHeading(h.textContent || '');
+      if (!base) return;
+      var id = base;
+      var n = seen[base] || 0;
+      if (n) id = base + '-' + n;
+      seen[base] = n + 1;
+      h.id = id;
+    });
+  }
+
+  function scrollReaderToHash(hash) {
+    var body = $('docs-reader-body');
+    var reader = $('docs-reader');
+    if (!body || !reader || !hash) return false;
+    var id = String(hash).replace(/^#/, '');
+    if (!id) return false;
+    var target = document.getElementById(id);
+    if (!target || !body.contains(target)) return false;
+    reader.scrollTop = target.offsetTop - body.offsetTop - 8;
+    return true;
+  }
+
   function loadTree() {
     if (_treeLoaded) return;
     fetch('/api/admin/docs/tree', { headers: getAuthHeaders() })
@@ -152,6 +189,7 @@
           return;
         }
         body.innerHTML = data.html || '';
+        prepareDocAnchors(body);
         if (meta) {
           meta.textContent = relPath + '   •   ' + (data.bytes != null ? (data.bytes + ' bytes') : '');
         }
@@ -160,6 +198,7 @@
         // Scroll content area to top so deep-link readers don't land mid-doc
         var reader = $('docs-reader');
         if (reader) reader.scrollTop = 0;
+        if (window.location.hash) setTimeout(function () { scrollReaderToHash(window.location.hash); }, 0);
       })
       .catch(function (err) {
         body.innerHTML = '<p style="color:var(--red);">' + escHtml(err.message || String(err)) + '</p>';
@@ -203,6 +242,15 @@
           arrow.classList.toggle('fa-chevron-right', !willOpen);
         }
         persistExpanded();
+        return;
+      }
+      var docLink = e.target.closest('#docs-reader-body a[href^="#"]');
+      if (docLink) {
+        var href = docLink.getAttribute('href');
+        if (href && scrollReaderToHash(href)) {
+          e.preventDefault();
+          try { history.replaceState(null, '', href); } catch (_) { window.location.hash = href; }
+        }
       }
     });