Settings polish: /setup provider subs, Add API defaults to api kind, picker shows offline endpoints, doc library tracks sub-tab

- /setup gains explicit provider subcommands (deepseek, openai,
  anthropic, openrouter, groq, gemini, xai, ollama, copilot, local,
  endpoint) so the autocomplete popup surfaces "/setup de…" suggestions
  with format hints, and bare-provider invocations still prompt for
  the key.
- Add API endpoint defaults to kind=api (auto-refresh /v1/models)
  instead of kind=proxy. Proxy was a frequent footgun for OpenAI-
  compatible endpoints that DO serve /v1/models — the user got an
  empty model list and had to flip the dropdown.
- Model picker now includes offline endpoints with stale:true so a
  briefly-down local server doesn't vanish from the picker (it dims
  and shows the offline pill, clickable anyway). Dedup prefers the
  online entry when the same model is exposed by both.
- Document library modal header reflects the active sub-tab via
  _TAB_HEADERS so it no longer shows the wrong section name when
  switching between Documents / Skills / Templates.

static/js/documentLibrary.js

@@ -1598,7 +1598,11 @@ let _libraryArchivedView = false;   // Documents tab showing archived docs?
     modal.innerHTML = `
       <div class="modal-content doclib-modal-content" style="width:min(640px, 92vw);max-height:85vh;background:var(--bg);">
         <div class="modal-header">
-          <h4><svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" style="vertical-align:-2px;margin-right:4px;"><path d="M4 19.5A2.5 2.5 0 0 1 6.5 17H20"/><path d="M6.5 2H20v20H6.5A2.5 2.5 0 0 1 4 19.5v-15A2.5 2.5 0 0 1 6.5 2z"/><line x1="8" y1="7" x2="16" y2="7"/><line x1="8" y1="11" x2="14" y2="11"/></svg>Library</h4>
+          <!-- Header title + icon mirror the currently-active sub-tab (Chats /
+               Documents / Research / Archive) so the user sees ONE icon at
+               the top representing the section they're in, with the tab
+               strip below as sub-navigation. _switchLibTab() updates this. -->
+          <h4 id="doclib-header-title"><span id="doclib-header-icon" style="vertical-align:-2px;margin-right:4px;display:inline-flex;"></span><span id="doclib-header-text">Library</span></h4>
           <button class="close-btn" id="doclib-close">\u2716</button>
         </div>
         <div class="lib-tabs" id="doclib-lib-tabs" style="padding:0 10px;">
@@ -1831,6 +1835,27 @@ let _libraryArchivedView = false;   // Documents tab showing archived docs?
       grid.parentElement.appendChild(btn);
     }
 
+    // SVG markup + label for each tab — used to keep the modal header
+    // in sync with whichever sub-tab the user is on.
+    const _TAB_HEADERS = {
+      chats: {
+        label: 'Chats',
+        svg: '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z"/></svg>',
+      },
+      documents: {
+        label: 'Documents',
+        svg: '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"/><polyline points="14 2 14 8 20 8"/><line x1="8" y1="13" x2="16" y2="13"/><line x1="8" y1="17" x2="13" y2="17"/></svg>',
+      },
+      research: {
+        label: 'Research',
+        svg: '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="11" cy="11" r="8"/><path d="M21 21l-4.35-4.35"/><line x1="11" y1="8" x2="11" y2="14"/><line x1="8" y1="11" x2="14" y2="11"/></svg>',
+      },
+      archive: {
+        label: 'Archive',
+        svg: '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="21 8 21 21 3 21 3 8"/><rect x="1" y="3" width="22" height="5"/><line x1="10" y1="12" x2="14" y2="12"/></svg>',
+      },
+    };
+
     function _switchLibTab(tab) {
       _activeLibTab = tab;
       _tabBtns.forEach(b => b.classList.toggle('active', b.dataset.doclibTab === tab));
@@ -1841,6 +1866,14 @@ let _libraryArchivedView = false;   // Documents tab showing archived docs?
           p.style.display = 'none';
         }
       });
+      // Sync the modal header icon + label to match the active sub-tab.
+      const hdr = _TAB_HEADERS[tab];
+      if (hdr) {
+        const ico = document.getElementById('doclib-header-icon');
+        const txt = document.getElementById('doclib-header-text');
+        if (ico) ico.innerHTML = hdr.svg;
+        if (txt) txt.textContent = hdr.label;
+      }
       if (tab === 'chats') _renderLibChats();
       else if (tab === 'archive') _renderLibArchive();
       else if (tab === 'research') _renderLibResearch();
@@ -3121,8 +3154,10 @@ let _libraryArchivedView = false;   // Documents tab showing archived docs?
       return new Date(iso).toLocaleDateString();
     }
 
-    // Switch to initial tab if not documents
-    if (_activeLibTab !== 'documents') _switchLibTab(_activeLibTab);
+    // Switch to the initial tab. Always call this — even when the
+    // default ('documents') matches — so the modal header's icon + label
+    // sync from "Library" to the active sub-tab on first open.
+    _switchLibTab(_activeLibTab);
 
     const searchInput = document.getElementById('doclib-search');
     searchInput.addEventListener('input', () => {