feat: move toggle to toolbar, sort apps by name, overlay expand

- Move expand/collapse toggle from stat strip to dedicated toolbar
  below KPIs
- Sort app groups alphabetically by name
- Expanded card overlays from clicked card position instead of
  pushing other cards down
- Viewport constraint: overlay flips right-alignment and limits
  height when near edges

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/pages/AgentHealth/AgentHealth.module.css

@@ -13,7 +13,7 @@
 /* Stat strip */
 .statStrip {
   display: grid;
-  grid-template-columns: repeat(5, 1fr) auto;
+  grid-template-columns: repeat(5, 1fr);
   gap: 10px;
   margin-bottom: 16px;
 }
@@ -99,6 +99,7 @@
   grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
   gap: 10px;
   margin-bottom: 20px;
+  position: relative;
 }
 
 /* Group meta row */
@@ -317,25 +318,49 @@
   color: var(--card-accent);
 }
 
-/* Expanded card inside compact grid */
+/* Wrapper for each compact grid cell — anchor for overlay */
+.compactGridCell {
+  position: relative;
+}
+
+/* Expanded card overlay — floats from the clicked card */
 .compactGridExpanded {
-  grid-column: span 2;
+  position: absolute;
+  z-index: 10;
+  top: 0;
+  left: 0;
+  min-width: 500px;
+  background: var(--bg-body);
+  border-radius: var(--radius-md);
+  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
+  padding: 4px;
 }
 
 /* Expand/collapse animation wrapper */
 .expandWrapper {
   overflow: hidden;
-  transition: max-height 200ms ease, opacity 150ms ease;
+  transition: opacity 200ms ease, transform 200ms ease;
 }
 
 .expandWrapperCollapsed {
-  max-height: 0;
   opacity: 0;
+  transform: scaleY(0.95);
+  transform-origin: top;
 }
 
 .expandWrapperExpanded {
-  max-height: 1000px;
   opacity: 1;
+  transform: scaleY(1);
+  transform-origin: top;
+}
+
+/* View toolbar — between stat strip and cards grid */
+.viewToolbar {
+  display: flex;
+  align-items: center;
+  justify-content: flex-end;
+  gap: 8px;
+  margin-bottom: 12px;
 }
 
 /* View mode toggle */

ui/src/pages/AgentHealth/AgentHealth.tsx

@@ -289,7 +289,7 @@ export default function AgentHealth() {
 
   const agentList = agents ?? [];
 
-  const groups = useMemo(() => groupByApp(agentList), [agentList]);
+  const groups = useMemo(() => groupByApp(agentList).sort((a, b) => a.appId.localeCompare(b.appId)), [agentList]);
 
   // Aggregate stats
   const totalInstances = agentList.length;
@@ -515,6 +515,10 @@ export default function AgentHealth() {
           accent={deadCount > 0 ? 'error' : 'success'}
           detail={deadCount > 0 ? 'requires attention' : 'all healthy'}
         />
+      </div>
+
+      {/* View toolbar */}
+      <div className={styles.viewToolbar}>
         <div className={styles.viewToggle}>
           <button
             className={`${styles.viewToggleBtn} ${viewMode === 'compact' ? styles.viewToggleBtnActive : ''}`}
@@ -702,85 +706,99 @@ export default function AgentHealth() {
         </div>
       ) : (
         <div className={styles.compactGrid}>
-          {groups.map((group) =>
-            expandedApps.has(group.appId) ? (
-              <div
-                key={group.appId}
-                className={`${styles.compactGridExpanded} ${styles.expandWrapper} ${
-                  animatingApps.get(group.appId) === 'expanding'
-                    ? styles.expandWrapperCollapsed
-                    : animatingApps.get(group.appId) === 'collapsing'
-                      ? styles.expandWrapperCollapsed
-                      : styles.expandWrapperExpanded
-                }`}
-              >
-                <GroupCard
-                  title={group.appId}
-                  accent={appHealth(group)}
-                  headerRight={
-                    <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
-                      <Badge
-                        label={`${group.liveCount}/${group.instances.length} LIVE`}
-                        color={appHealth(group)}
-                        variant="filled"
-                      />
-                      <button
-                        className={styles.collapseBtn}
-                        onClick={() => animateToggle(group.appId)}
-                        title="Collapse"
-                      >
-                        <ChevronDown size={14} />
-                      </button>
-                    </div>
-                  }
-                  meta={
-                    <div className={styles.groupMeta}>
-                      <span><strong>{group.totalTps.toFixed(1)}</strong> msg/s</span>
-                      <span><strong>{group.totalActiveRoutes}</strong>/{group.totalRoutes} routes</span>
-                      <span>
-                        <StatusDot
-                          variant={
-                            appHealth(group) === 'success'
-                              ? 'live'
-                              : appHealth(group) === 'warning'
-                                ? 'stale'
-                                : 'dead'
-                          }
-                        />
-                      </span>
-                    </div>
-                  }
-                  footer={
-                    group.deadCount > 0 ? (
-                      <div className={styles.alertBanner}>
-                        <span className={styles.alertIcon}>&#9888;</span>
-                        <span>
-                          Single point of failure &mdash;{' '}
-                          {group.deadCount === group.instances.length
-                            ? 'no redundancy'
-                            : `${group.deadCount} dead instance${group.deadCount > 1 ? 's' : ''}`}
-                        </span>
-                      </div>
-                    ) : undefined
-                  }
-                >
-                  <DataTable<AgentInstance & { id: string }>
-                    columns={instanceColumns as Column<AgentInstance & { id: string }>[]}
-                    data={group.instances.map(i => ({ ...i, id: i.instanceId }))}
-                    onRowClick={handleInstanceClick}
-                    pageSize={50}
-                    flush
-                  />
-                </GroupCard>
-              </div>
-            ) : (
+          {groups.map((group) => (
+            <div key={group.appId} className={styles.compactGridCell}>
               <CompactAppCard
-                key={group.appId}
                 group={group}
                 onExpand={() => animateToggle(group.appId)}
               />
-            ),
-          )}
+              {expandedApps.has(group.appId) && (
+                <div
+                  ref={(el) => {
+                    if (!el) return;
+                    // Constrain overlay within viewport
+                    const rect = el.getBoundingClientRect();
+                    const vw = document.documentElement.clientWidth;
+                    if (rect.right > vw - 16) {
+                      el.style.left = 'auto';
+                      el.style.right = '0';
+                    }
+                    if (rect.bottom > document.documentElement.clientHeight) {
+                      const overflow = rect.bottom - document.documentElement.clientHeight + 16;
+                      el.style.maxHeight = `${rect.height - overflow}px`;
+                      el.style.overflowY = 'auto';
+                    }
+                  }}
+                  className={`${styles.compactGridExpanded} ${styles.expandWrapper} ${
+                    animatingApps.get(group.appId) === 'expanding'
+                      ? styles.expandWrapperCollapsed
+                      : animatingApps.get(group.appId) === 'collapsing'
+                        ? styles.expandWrapperCollapsed
+                        : styles.expandWrapperExpanded
+                  }`}
+                >
+                  <GroupCard
+                    title={group.appId}
+                    accent={appHealth(group)}
+                    headerRight={
+                      <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
+                        <Badge
+                          label={`${group.liveCount}/${group.instances.length} LIVE`}
+                          color={appHealth(group)}
+                          variant="filled"
+                        />
+                        <button
+                          className={styles.collapseBtn}
+                          onClick={() => animateToggle(group.appId)}
+                          title="Collapse"
+                        >
+                          <ChevronDown size={14} />
+                        </button>
+                      </div>
+                    }
+                    meta={
+                      <div className={styles.groupMeta}>
+                        <span><strong>{group.totalTps.toFixed(1)}</strong> msg/s</span>
+                        <span><strong>{group.totalActiveRoutes}</strong>/{group.totalRoutes} routes</span>
+                        <span>
+                          <StatusDot
+                            variant={
+                              appHealth(group) === 'success'
+                                ? 'live'
+                                : appHealth(group) === 'warning'
+                                  ? 'stale'
+                                  : 'dead'
+                            }
+                          />
+                        </span>
+                      </div>
+                    }
+                    footer={
+                      group.deadCount > 0 ? (
+                        <div className={styles.alertBanner}>
+                          <span className={styles.alertIcon}>&#9888;</span>
+                          <span>
+                            Single point of failure &mdash;{' '}
+                            {group.deadCount === group.instances.length
+                              ? 'no redundancy'
+                              : `${group.deadCount} dead instance${group.deadCount > 1 ? 's' : ''}`}
+                          </span>
+                        </div>
+                      ) : undefined
+                    }
+                  >
+                    <DataTable<AgentInstance & { id: string }>
+                      columns={instanceColumns as Column<AgentInstance & { id: string }>[]}
+                      data={group.instances.map(i => ({ ...i, id: i.instanceId }))}
+                      onRowClick={handleInstanceClick}
+                      pageSize={50}
+                      flush
+                    />
+                  </GroupCard>
+                </div>
+              )}
+            </div>
+          ))}
         </div>
       )}