refactor: normalize branch name handling and enhance auto mode settings merging

- Updated branch name normalization to align with UI conventions, treating "main" as null for consistency.
- Implemented deep merging of `autoModeByWorktree` settings to preserve existing entries during updates.
- Enhanced the BoardView component to persist max concurrency settings to the server, ensuring accurate capacity checks.
- Added error handling for feature rollback persistence in useBoardActions.

These changes improve the reliability and consistency of auto mode settings across the application.

apps/ui/src/components/views/board-view.tsx

@@ -87,6 +87,7 @@ import { usePipelineConfig } from '@/hooks/queries';
 import { useQueryClient } from '@tanstack/react-query';
 import { queryKeys } from '@/lib/query-keys';
 import { useAutoModeQueryInvalidation } from '@/hooks/use-query-invalidation';
+import { useUpdateGlobalSettings } from '@/hooks/mutations/use-settings-mutations';
 
 // Stable empty array to avoid infinite loop in selector
 const EMPTY_WORKTREES: ReturnType<ReturnType<typeof useAppStore.getState>['getWorktrees']> = [];
@@ -451,6 +452,8 @@ export function BoardView() {
   const maxConcurrency = autoMode.maxConcurrency;
   // Get worktree-specific setter
   const setMaxConcurrencyForWorktree = useAppStore((state) => state.setMaxConcurrencyForWorktree);
+  // Mutation to persist maxConcurrency to server settings
+  const updateGlobalSettings = useUpdateGlobalSettings({ showSuccessToast: false });
 
   // Get the current branch from the selected worktree (not from store which may be stale)
   const currentWorktreeBranch = selectedWorktree?.branch ?? null;
@@ -1277,6 +1280,15 @@ export function BoardView() {
           if (currentProject && selectedWorktree) {
             const branchName = selectedWorktree.isMain ? null : selectedWorktree.branch;
             setMaxConcurrencyForWorktree(currentProject.id, branchName, newMaxConcurrency);
+
+            // Persist to server settings so capacity checks use the correct value
+            const worktreeKey = `${currentProject.id}::${branchName ?? '__main__'}`;
+            updateGlobalSettings.mutate({
+              autoModeByWorktree: {
+                [worktreeKey]: { maxConcurrency: newMaxConcurrency },
+              },
+            });
+
             // Also update backend if auto mode is running
             if (autoMode.isRunning) {
               // Restart auto mode with new concurrency (backend will handle this)

apps/ui/src/components/views/board-view/hooks/use-board-actions.ts

@@ -553,6 +553,11 @@ export function useBoardActions({
         };
         updateFeature(feature.id, rollbackUpdates);
 
+        // Also persist the rollback so it survives page refresh
+        persistFeatureUpdate(feature.id, rollbackUpdates).catch((persistError) => {
+          logger.error('Failed to persist rollback:', persistError);
+        });
+
         // If server is offline (connection refused), redirect to login page
         if (isConnectionError(error)) {
           handleServerOffline();