Cookbook UI: Ollama browser, advanced serve fold, API tokens form, diagnosis toolbar, polish

Surface a lot of accumulated cookbook + UI work as a single non-agent
commit so the agent rework lands cleanly.

Highlights:
- Ollama as a first-class backend in the Cookbook:
  * Download input accepts ollama-style names (name:tag) → backend=ollama
  * /api/cookbook/ollama/library (cached scrape of ollama.com + curated
    fallback so classic models like qwen2.5 stay reachable)
  * "Browse Ollama library" toggle below Download with size chips
  * Engine=Ollama in hwfit toolbar merges the Ollama library into the
    main scan list as per-tag rows with the same Fit/Param/Quant/VRAM
    columns; click → fills Download input
- API Tokens form added to Integrations panel (matching wired
  loadTokens()/initTokenForm() that had no HTML)
- Serve panel polish: Advanced fold tightening (-8px nudges on vLLM
  checks, Extra args, Spec row), n_cpu_moe + Split Mode controls
  pulled up 8px to align with the row's checkboxes, GGUF File dropdown
  exposed for Ollama backend, GPU re-render on Edit serve restore,
  _forceBackend flag so saved serveState wins over backend detection,
  cookbook:servers-changed CustomEvent so panels don't need refresh
- Models page redesign: Add Models row (URL + hidden API key reveal +
  Type select + Scan/Ollama/Key/Test/Add icon buttons), Probe All +
  Clear-offline buttons in Added Models toolbar, offline-pill removed
  (opacity already conveys state), Engine dropdown gains Ollama option
- _ping_endpoint probes /v1/models then base, accepts 4xx as
  reachable (vLLM returns 404 on bare /v1, fully working endpoints
  were showing offline)
- Diagnosis card: × dismiss + Copy bundle buttons restored on the
  serve error feedback card
- Orphan tmux sweep re-enabled behind a 60s rate-limit + background
  Thread (off the main event loop) so dead serves get discovered
- cookbook_routes auto-register watchdog: drops the endpoint if the
  serve session exits non-zero within the first ~3min
- ollama-rocm sidecar awareness in download wrapper (`docker exec
  ollama-rocm ollama pull` when host ollama isn't installed)
- Skill extractor sets initial_status="published" when
  auto_approve_skills pref is on (audit demotes later)
- Skill list / model list / cookbook scan misc polish

static/js/modelPicker.js

@@ -327,13 +327,10 @@ function _initModelPickerDropdown() {
       // hover so the suffix/variant tag is still discoverable (#1982).
       nameSpan.title = m.display;
       row.appendChild(nameSpan);
-      if (m.stale) {
-        const badge = document.createElement('span');
-        badge.className = 'model-switch-stale-badge';
-        badge.textContent = 'offline';
-        badge.style.cssText = 'font-size:10px;opacity:0.7;padding:1px 6px;border:1px solid var(--border);border-radius:8px;margin-left:6px;';
-        row.appendChild(badge);
-      }
+      // Offline state is already conveyed by the row's reduced opacity —
+      // a redundant "offline" pill on top of that just added clutter.
+      // (Class kept on `row` so the opacity rule still applies; the text
+      // badge is gone.)
       const epSpan = document.createElement('span');
       epSpan.className = 'model-switch-ep';
       // Don't show endpoint name if it matches the model name (local self-hosted)