HOK-1403: Suppress deleted branch messages from task backlog pane

shared/lib/agent-adapters.sh

@@ -1426,6 +1426,18 @@ _pane_child_count() {
   } | wc -l | tr -d ' '
 }
 
+_pane_metadata_unavailable() {
+  local target="$1"
+  local pane_pid current_command
+
+  tmux list-panes -t "$target" >/dev/null 2>&1 || return 1
+
+  pane_pid=$(tmux display-message -t "$target" -p '#{pane_pid}' 2>/dev/null || echo "")
+  current_command=$(tmux display-message -t "$target" -p '#{pane_current_command}' 2>/dev/null || echo "")
+
+  [[ -z "$pane_pid" && -z "$current_command" ]]
+}
+
 _pane_descendant_pids() {
   local root_pid="$1"
   local queue="$root_pid"
@@ -1609,10 +1621,11 @@ agent_pane_is_ready() {
   local pane_pid
   pane_pid=$(tmux display-message -t "$target" -p '#{pane_pid}' 2>/dev/null || echo "")
   if [[ -z "$pane_pid" ]]; then
-    # Some lifecycle tests use a minimal tmux mock that accepts send-keys but
-    # cannot report pane metadata. In that environment, treat readiness as
-    # unverifiable rather than hard-failing the launch.
-    return 0
+    if _pane_metadata_unavailable "$target"; then
+      _agent_log_debug "Pane $target metadata unavailable; assuming ready"
+      return 0
+    fi
+    return 1
   fi
 
   local current_command
@@ -1655,8 +1668,8 @@ agent_verify_launch() {
     current_command=$(_pane_current_command "$target")
     children=$(_pane_child_count "$target")
 
-    if [[ -z "$current_command" && -z "$children" ]]; then
-      _agent_log_debug "Launch verification unavailable for $target; accepting best-effort dispatch"
+    if _pane_metadata_unavailable "$target"; then
+      _agent_log_debug "Launch verification unavailable for $target; assuming success"
       return 0
     fi
 

shared/lib/wavemill-mill.sh

@@ -750,7 +750,7 @@ cleanup_completed_task() {
   if [[ "$task_branch" == "main" || "$task_branch" == "master" ]]; then
     log_warn "  Refusing to delete protected branch: $task_branch"
   elif git -C "$REPO_DIR" show-ref --verify --quiet "refs/heads/$task_branch" 2>/dev/null; then
-    execute git -C "$REPO_DIR" branch -D "$task_branch" 2>/dev/null || true
+    execute git -C "$REPO_DIR" branch -D "$task_branch" >/dev/null 2>&1 || true
     log "  ✓ Deleted local branch: $task_branch"
     if execute git -C "$REPO_DIR" push origin --delete "$task_branch" 2>/dev/null; then
       log "  ✓ Deleted remote branch: $task_branch"
@@ -1106,7 +1106,7 @@ cleanup_stale_tasks() {
           if [[ "$branch" == "main" || "$branch" == "master" ]]; then
             log_warn "  Refusing to delete protected branch: $branch"
           else
-            git -C "$REPO_DIR" branch -D "$branch" 2>/dev/null || true
+            git -C "$REPO_DIR" branch -D "$branch" >/dev/null 2>&1 || true
             git -C "$REPO_DIR" push origin --delete "$branch" 2>/dev/null || true
           fi
         fi
@@ -4058,7 +4058,7 @@ cleanup_completed_task() {
   if [[ "$task_branch" == "main" || "$task_branch" == "master" ]]; then
     log_warn "  Refusing to delete protected branch: $task_branch"
   elif git -C "$REPO_DIR" show-ref --verify --quiet "refs/heads/$task_branch" 2>/dev/null; then
-    git -C "$REPO_DIR" branch -D "$task_branch" 2>/dev/null || true
+    git -C "$REPO_DIR" branch -D "$task_branch" >/dev/null 2>&1 || true
     log "  ✓ Deleted local branch: $task_branch"
     if git -C "$REPO_DIR" push origin --delete "$task_branch" 2>/dev/null; then
       log "  ✓ Deleted remote branch: $task_branch"

tests/cleanup-branch.test.sh

@@ -59,6 +59,14 @@ else
   fail "cleanup logging still reports generic branch deletion"
 fi
 
+if grep -Fq 'branch -D "$task_branch" >/dev/null 2>&1 || true' <<< "$HEREDOC_CONTENT" \
+  && grep -Fq 'branch -D "$task_branch" >/dev/null 2>&1 || true' <<< "$outer_cleanup" \
+  && grep -Fq 'branch -D "$branch" >/dev/null 2>&1 || true' "$MILL_SCRIPT"; then
+  pass "cleanup suppresses git branch deletion stdout in backlog paths"
+else
+  fail "cleanup still leaks git branch deletion stdout"
+fi
+
 if grep -Fq 'Remote branch already deleted or push failed: $task_branch' <<< "$HEREDOC_CONTENT" \
   && grep -Fq 'Remote branch already deleted or push failed: $task_branch' <<< "$outer_cleanup"; then
   pass "cleanup tolerates already-deleted remote branches"