C4/D11 follow-up - the integration review's seven confirmed findings

An adversarial review (four lenses, every finding independently verified by two
skeptics told to refute it) ran over 2a5f6b3 and 8cf8c0f. Seven findings
survived; all seven are fixed here.

Against the C4 fix:
- help.js: the nav hover was renamed onto its own surface token, keeping a
  no-op T9.9 had introduced (two different grays had been mapped to one name).
  Hover is now --cds-layer-hover, the token that exists for exactly this.
- wp-creation-app.js: the drawer's critical CSS pre-painted --cds-layer-accent
  while the stylesheet paints --wp-nav-bg; now both paint --wp-nav-bg.

Against D11:
- wp-sections.js: the Assets toggle note still described the pre-D11 card
  ('Asset tags and controls.dev links') with a rationale the picker inverts.
- runAssetSearch: the result cap counted contains-matches before the exact and
  prefix tiers finished, so 500 alphabetically-early substring hits could evict
  the exact match - and Enter then added the wrong asset, ID-locked. The cap
  now bounds each tier; the scan always sees the whole catalog.
- addCatalogAsset: the one mutation in the section with no announced outcome
  was the successful pick. It now toasts (role=status), matching every sibling
  path (C1).
- assets_db.py: failures are remembered for FAIL_CACHE_SECONDS (default 30s)
  and a stale catalog is served over an error, so a Micron outage costs one
  CONNECT_TIMEOUT per window instead of one per page load stacking up in the
  shared sync threadpool until login itself stalls.
- assets_db.py: MICRON_ASSETS_CACHE_SECONDS='5m' no longer crashes the boot -
  a malformed knob on an OPTIONAL feature degrades to its default, loudly.

assets_check grows four regressions for these (27 -> 31): per-tier cap against
600 decoys, the announced pick, boot with a malformed knob, and the stable
cached 503. Battery: assets_check 31/31, color_check 5/5, sections_check ALL
PASS.

Items: C4, D11.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

html/wp-creation-app.js

@@ -1444,12 +1444,16 @@ function runAssetSearch(q){
     assetResults = []; renderAssetResults(); openAssetResults(false); return;
   }
   const exact=[], prefix=[], other=[];
+  // The cap bounds each TIER, never the scan: breaking on a combined count let
+  // 500 alphabetically-early contains-matches evict an exact or prefix match
+  // that sorted after them - and Enter then added the wrong asset. The scan is
+  // in-memory and cheap; "the box scrolls, not the search" means the search
+  // sees everything.
   for(const tag of assetCatalog){
     const t = tag.toLowerCase();
     if(t === q) exact.push(tag);
-    else if(t.startsWith(q)) prefix.push(tag);
-    else if(t.includes(q)) other.push(tag);
-    if(exact.length + prefix.length + other.length >= ASSET_RESULT_MAX) break;
+    else if(t.startsWith(q)){ if(prefix.length < ASSET_RESULT_MAX) prefix.push(tag); }
+    else if(t.includes(q)){ if(other.length < ASSET_RESULT_MAX) other.push(tag); }
   }
   assetResults = exact.concat(prefix, other).slice(0, ASSET_RESULT_MAX);
   renderAssetResults();
@@ -1483,6 +1487,7 @@ function addCatalogAsset(ix){
   if(assetAlreadyAdded(tag)){ toast('That asset is already on this package'); return; }
   pkgAssets.push({ tag: tag, desc: '', link: '', source: 'catalog' });
   buildAssets();
+  toast('Added ' + tag);   // announced (role=status) - a keyboard pick is otherwise silent
   // Mark just this row instead of re-rendering the list: the results stay open
   // for the next pick, the scroll position holds, and the clicked element is
   // never detached mid-click (see the composedPath note in initAssetPicker).
@@ -2929,7 +2934,7 @@ const WP_NAV_CRITICAL_CSS = `
   body{--nav-w:288px;}
   body.wp-nav-collapsed{--nav-w:56px;}
   .wp-nav{position:fixed;top:var(--rail-top,48px);left:0;bottom:0;width:var(--nav-w);
-    z-index:120;display:flex;flex-direction:column;overflow:hidden;background:var(--cds-layer-accent);
+    z-index:120;display:flex;flex-direction:column;overflow:hidden;background:var(--wp-nav-bg);
     border-right:1px solid var(--cds-border-subtle);}
   .wp-nav-list{flex:1 1 auto;overflow-y:auto;overflow-x:hidden;}
   .wp-nav-item,.wp-nav-link{display:flex;align-items:center;gap:11px;width:100%;