fix: merge worktree handler now uses correct branch name and path

The merge handler previously hardcoded branch names as `feature/${featureId}`
and worktree paths as `.worktrees/${featureId}`, which failed for auto-generated
branches (e.g., `feature/v0.11.0rc-1768413895104-31pa`) and custom worktrees.

Changes:
- Server handler now accepts branchName and worktreePath directly from the UI
- Added branch existence validation before attempting merge
- Updated merge dialog with 2-step confirmation (type "merge" to confirm)
- Removed feature branch naming restriction - any branch can now be merged
- Updated API types and client to pass correct parameters

Closes #408

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/ui/src/components/views/board-view/worktree-panel/components/worktree-actions-dropdown.tsx

@@ -55,6 +55,7 @@ interface WorktreeActionsDropdownProps {
   onCreatePR: (worktree: WorktreeInfo) => void;
   onAddressPRComments: (worktree: WorktreeInfo, prInfo: PRInfo) => void;
   onResolveConflicts: (worktree: WorktreeInfo) => void;
+  onMerge: (worktree: WorktreeInfo) => void;
   onDeleteWorktree: (worktree: WorktreeInfo) => void;
   onStartDevServer: (worktree: WorktreeInfo) => void;
   onStopDevServer: (worktree: WorktreeInfo) => void;
@@ -84,6 +85,7 @@ export function WorktreeActionsDropdown({
   onCreatePR,
   onAddressPRComments,
   onResolveConflicts,
+  onMerge,
   onDeleteWorktree,
   onStartDevServer,
   onStopDevServer,
@@ -231,6 +233,27 @@ export function WorktreeActionsDropdown({
             {!canPerformGitOps && <AlertCircle className="w-3 h-3 ml-auto text-muted-foreground" />}
           </DropdownMenuItem>
         </TooltipWrapper>
+        {!worktree.isMain && (
+          <TooltipWrapper
+            showTooltip={!!gitOpsDisabledReason}
+            tooltipContent={gitOpsDisabledReason}
+          >
+            <DropdownMenuItem
+              onClick={() => canPerformGitOps && onMerge(worktree)}
+              disabled={!canPerformGitOps}
+              className={cn(
+                'text-xs text-green-600 focus:text-green-700',
+                !canPerformGitOps && 'opacity-50 cursor-not-allowed'
+              )}
+            >
+              <GitMerge className="w-3.5 h-3.5 mr-2" />
+              Merge to Main
+              {!canPerformGitOps && (
+                <AlertCircle className="w-3 h-3 ml-auto text-muted-foreground" />
+              )}
+            </DropdownMenuItem>
+          </TooltipWrapper>
+        )}
         <DropdownMenuSeparator />
         {/* Open in editor - split button: click main area for default, chevron for other options */}
         {effectiveDefaultEditor && (

apps/ui/src/components/views/board-view/worktree-panel/components/worktree-tab.tsx

@@ -41,6 +41,7 @@ interface WorktreeTabProps {
   onCreatePR: (worktree: WorktreeInfo) => void;
   onAddressPRComments: (worktree: WorktreeInfo, prInfo: PRInfo) => void;
   onResolveConflicts: (worktree: WorktreeInfo) => void;
+  onMerge: (worktree: WorktreeInfo) => void;
   onDeleteWorktree: (worktree: WorktreeInfo) => void;
   onStartDevServer: (worktree: WorktreeInfo) => void;
   onStopDevServer: (worktree: WorktreeInfo) => void;
@@ -84,6 +85,7 @@ export function WorktreeTab({
   onCreatePR,
   onAddressPRComments,
   onResolveConflicts,
+  onMerge,
   onDeleteWorktree,
   onStartDevServer,
   onStopDevServer,
@@ -344,6 +346,7 @@ export function WorktreeTab({
         onCreatePR={onCreatePR}
         onAddressPRComments={onAddressPRComments}
         onResolveConflicts={onResolveConflicts}
+        onMerge={onMerge}
         onDeleteWorktree={onDeleteWorktree}
         onStartDevServer={onStartDevServer}
         onStopDevServer={onStopDevServer}

apps/ui/src/components/views/board-view/worktree-panel/types.ts

@@ -73,6 +73,7 @@ export interface WorktreePanelProps {
   onCreateBranch: (worktree: WorktreeInfo) => void;
   onAddressPRComments: (worktree: WorktreeInfo, prInfo: PRInfo) => void;
   onResolveConflicts: (worktree: WorktreeInfo) => void;
+  onMerge: (worktree: WorktreeInfo) => void;
   onRemovedWorktrees?: (removedWorktrees: Array<{ path: string; branch: string }>) => void;
   runningFeatureIds?: string[];
   features?: FeatureInfo[];

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

@@ -30,6 +30,7 @@ export function WorktreePanel({
   onCreateBranch,
   onAddressPRComments,
   onResolveConflicts,
+  onMerge,
   onRemovedWorktrees,
   runningFeatureIds = [],
   features = [],
@@ -248,10 +249,12 @@ export function WorktreePanel({
             onCreatePR={onCreatePR}
             onAddressPRComments={onAddressPRComments}
             onResolveConflicts={onResolveConflicts}
+            onMerge={onMerge}
             onDeleteWorktree={onDeleteWorktree}
             onStartDevServer={handleStartDevServer}
             onStopDevServer={handleStopDevServer}
             onOpenDevServerUrl={handleOpenDevServerUrl}
+            onViewDevServerLogs={handleViewDevServerLogs}
             onRunInitScript={handleRunInitScript}
             hasInitScript={hasInitScript}
           />
@@ -333,6 +336,7 @@ export function WorktreePanel({
             onCreatePR={onCreatePR}
             onAddressPRComments={onAddressPRComments}
             onResolveConflicts={onResolveConflicts}
+            onMerge={onMerge}
             onDeleteWorktree={onDeleteWorktree}
             onStartDevServer={handleStartDevServer}
             onStopDevServer={handleStopDevServer}
@@ -390,6 +394,7 @@ export function WorktreePanel({
                   onCreatePR={onCreatePR}
                   onAddressPRComments={onAddressPRComments}
                   onResolveConflicts={onResolveConflicts}
+                  onMerge={onMerge}
                   onDeleteWorktree={onDeleteWorktree}
                   onStartDevServer={handleStartDevServer}
                   onStopDevServer={handleStopDevServer}