fix: make Reduced motion gate overlays, standardize the tab band, and polish fleet/snapshots (#1504)

* fix: address review feedback on motion, fleet band, and snapshots

- Reduced motion now also skips the animate-ui overlay open/close animations
  (dialog, sheet, popover, dropdown-menu) via a shared useReducedTransition that
  zeroes the transition when reduced motion is active; MotionConfig alone only
  neutralized transform/layout, leaving the opacity/blur fade.
- Fleet tab band: flatten the list's own pill band so the tabs sit in a single
  full-width band instead of a nested second band.
- Fleet Overview: label the node-update button "Node Update"; the add-node
  button becomes a ChartNetwork icon that opens Settings > Nodes (outline style,
  matching the node-update button) instead of the add-node modal.
- Blueprint deployments empty state: drive the serif headings from the theme
  heading-style token so Calm drops the italic.
- Snapshots: move the per-stack Restore onto the stack header row (right side),
  matching the ghost action style.

* feat: standardize the tab band on Security and add a tab hover state

- Apply the Fleet full-width tab band to the Security page (single band, the
  list's pill background flattened so the tabs sit directly in it).
- Add a hover highlight to tabs so the band reads as interactive, not flat;
  the active tab is unaffected.

* fix: drive reduced-motion transitions from the app setting, not the OS query

useReducedTransition called framer-motion's useReducedMotion(), which only
reflects the OS prefers-reduced-motion media query and ignores our MotionConfig
/ appearance toggle, so dialogs kept animating with the setting on. Read the
app's useReducedMotion selector instead. Verified: with the setting on, the
dialog opacity snaps 0->1 in one frame; with it off, it ramps over the spring.

* feat: standardize stack-detail body text to text-xs and add a log expand toggle

- Bump the anatomy panel body text (rows, field values, warnings) and the
  structured log lines from 10/11/12px to text-xs (12px), leaving the uppercase
  kicker labels and the log level/source badges as-is.
- Add an expand control next to the log download button that collapses the
  Command Center so the logs pane fills the left column; toggles back to restore.

frontend/src/components/FleetView/OverviewToolbar.tsx

@@ -1,7 +1,7 @@
 import { useEffect, useMemo, useRef, useState } from 'react';
 import {
     Search, ArrowUpDown, AlertTriangle, Play, Square,
-    LayoutGrid, Network, SlidersHorizontal, Plus, RefreshCcwDot,
+    LayoutGrid, Network, SlidersHorizontal, ChartNetwork, RefreshCcwDot,
 } from 'lucide-react';
 import { Button } from '@/components/ui/button';
 import { Badge } from '@/components/ui/badge';
@@ -259,25 +259,27 @@ export function OverviewToolbar({
                 <Button
                     variant="outline"
                     size="sm"
-                    className="h-9 w-9 p-0 shrink-0"
+                    className="h-9 gap-2 shrink-0"
                     onClick={onCheckUpdates}
                     disabled={checkingUpdates}
-                    title="Check for updates"
-                    aria-label="Check for updates"
+                    title="Check for node updates"
+                    aria-label="Check for node updates"
                 >
                     <RefreshCcwDot className={`w-4 h-4 ${checkingUpdates ? 'animate-spin' : ''}`} />
+                    Node Update
                 </Button>
             )}
 
             {onAddNode && (
                 <Button
+                    variant="outline"
                     size="sm"
                     className="h-9 w-9 p-0 shrink-0"
                     onClick={onAddNode}
-                    title="Add node"
-                    aria-label="Add node"
+                    title="Manage nodes"
+                    aria-label="Manage nodes"
                 >
-                    <Plus className="w-4 h-4" strokeWidth={1.5} />
+                    <ChartNetwork className="w-4 h-4" strokeWidth={1.5} />
                 </Button>
             )}
         </div>

frontend/src/components/FleetView/__tests__/OverviewToolbar.test.tsx

@@ -82,32 +82,32 @@ describe('OverviewToolbar', () => {
     expect(screen.queryByText('Tags')).not.toBeInTheDocument();
   });
 
-  it('renders the Add node button and fires onAddNode when provided', () => {
+  it('renders the manage-nodes button and fires onAddNode when provided', () => {
     const onAddNode = vi.fn();
     render(<OverviewToolbar {...props({ onAddNode })} />);
-    fireEvent.click(screen.getByRole('button', { name: 'Add node' }));
+    fireEvent.click(screen.getByRole('button', { name: 'Manage nodes' }));
     expect(onAddNode).toHaveBeenCalledTimes(1);
   });
 
-  it('omits the Add node button when onAddNode is not provided', () => {
+  it('omits the manage-nodes button when onAddNode is not provided', () => {
     render(<OverviewToolbar {...props()} />);
-    expect(screen.queryByRole('button', { name: 'Add node' })).not.toBeInTheDocument();
+    expect(screen.queryByRole('button', { name: 'Manage nodes' })).not.toBeInTheDocument();
   });
 
   it('renders the Check Updates button and fires onCheckUpdates when provided', () => {
     const onCheckUpdates = vi.fn();
     render(<OverviewToolbar {...props({ onCheckUpdates })} />);
-    fireEvent.click(screen.getByRole('button', { name: /Check for updates/ }));
+    fireEvent.click(screen.getByRole('button', { name: /Check for node updates/ }));
     expect(onCheckUpdates).toHaveBeenCalledTimes(1);
   });
 
   it('omits the Check Updates button when onCheckUpdates is not provided', () => {
     render(<OverviewToolbar {...props()} />);
-    expect(screen.queryByRole('button', { name: /Check for updates/ })).not.toBeInTheDocument();
+    expect(screen.queryByRole('button', { name: /Check for node updates/ })).not.toBeInTheDocument();
   });
 
   it('disables the Check Updates button while a check is in flight', () => {
     render(<OverviewToolbar {...props({ onCheckUpdates: vi.fn(), checkingUpdates: true })} />);
-    expect(screen.getByRole('button', { name: /Check for updates/ })).toBeDisabled();
+    expect(screen.getByRole('button', { name: /Check for node updates/ })).toBeDisabled();
   });
 });