fix(studio): make remaining non-copyable error sites copyable

Audit sweep after the System-AI fix: the Settings dialog rendered its
two _error states as a bare Text (hub-endpoint save, default-scope
edit), and the Audit live-status bar showed the raw load failure in a
non-selectable Text (the only place that failure surfaces — the
empty-state below shows just a generic hint). Route the Settings errors
through ChainErrorBox and make the Audit disconnected text a
SelectableText. Errors must always be clipboard-copyable.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/pages/audit.dart

@@ -436,12 +436,26 @@ class _LiveStatusBar extends StatelessWidget {
             pulsing: live,
           ),
           const SizedBox(width: ChainSpace.sm),
-          Text(
+          // Disconnected → SelectableText so the raw error is copyable
-            live ? l.auditLiveStatus(eventCount) : l.auditDisconnected(error!),
+          // (it's the only place the underlying failure is surfaced;
-            style: theme.textTheme.bodySmall?.copyWith(
+          // the empty-state below shows only a generic hint).
-              color: theme.colorScheme.onSurfaceVariant,
+          if (live)
+            Text(
+              l.auditLiveStatus(eventCount),
+              style: theme.textTheme.bodySmall?.copyWith(
+                color: theme.colorScheme.onSurfaceVariant,
+              ),
+            )
+          else
+            Flexible(
+              child: SelectableText(
+                l.auditDisconnected(error!),
+                maxLines: 2,
+                style: theme.textTheme.bodySmall?.copyWith(
+                  color: theme.colorScheme.onSurfaceVariant,
+                ),
+              ),
             ),
-          ),
           const Spacer(),
           if (live)
             Row(

lib/widgets/chain_settings_dialog.dart

@@ -491,12 +491,8 @@ class _FaiSettingsDialogState extends State<ChainSettingsDialog> {
       ),
       if (_error != null) ...[
         const SizedBox(height: ChainSpace.md),
-        Text(
+        // Copyable — errors must be selectable + one-tap copyable.
-          _error!,
+        ChainErrorBox(text: _error!, isError: true, maxHeight: 200),
-          style: theme.textTheme.bodySmall?.copyWith(
-            color: theme.colorScheme.error,
-          ),
-        ),
       ],
       const SizedBox(height: ChainSpace.md),
       Container(
@@ -2490,12 +2486,8 @@ class _DefaultScopePanelState extends State<_DefaultScopePanel> {
           ],
           if (_error != null) ...[
             const SizedBox(height: ChainSpace.sm),
-            Text(
+            // Copyable — errors must be selectable + one-tap copyable.
-              _error!,
+            ChainErrorBox(text: _error!, isError: true, maxHeight: 200),
-              style: theme.textTheme.bodySmall?.copyWith(
-                color: theme.colorScheme.error,
-              ),
-            ),
           ],
         ],
       ],