fix(web): finish-review polish for the library view

Deterministic rail wrap on small screens (scrollbar-gutter plus
explicit order), aria-controls on the satisfied toggle, and the
toggle text aligned with the chip column's right edge.

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

web/index.html

@@ -120,6 +120,7 @@
           class="bucket-toggle readout"
           id="library-toggle"
           aria-expanded="false"
+          aria-controls="library-series library-movies"
           hidden
         ></button>
       </header>

web/src/style.css

@@ -97,6 +97,11 @@ body {
   padding: 0;
 }
 
+/* a scrollbar appearing must not reflow the rail's wrap */
+html {
+  scrollbar-gutter: stable;
+}
+
 body {
   min-height: 100dvh;
   display: flex;
@@ -993,6 +998,12 @@ body {
   margin: 0 0 var(--space-6);
 }
 
+/* the toggle's own padding would inset its text past the chip column's
+   right rag; drop it so SATISFIED sits flush with the chips below */
+.library-bar .bucket-toggle {
+  padding: 0;
+}
+
 /* ---- manual intake ---------------------------------------------------- */
 
 .intake .module-detail {
@@ -1018,6 +1029,17 @@ body {
     max-width: none;
   }
 
+  /* deterministic first row: identity, views, then meta pushed right —
+     never re-wrapped by content or scrollbar changes */
+  .rail-nav {
+    order: 2;
+  }
+
+  .rail-meta {
+    order: 2;
+    margin-left: auto;
+  }
+
   .deck {
     padding: var(--space-6) var(--space-4) var(--space-8);
   }