fix: accumulate message words instead of overwriting in cmd_continue

The for loop was overwriting message each iteration, causing only
the last word to survive. Changed to accumulate all words with
proper spacing.

Fixes #225

skills/kugetsu/scripts/kugetsu-session.sh

@@ -387,29 +387,6 @@ cmd_start() {
     echo "Worktree: $worktree_path"
 }
 
-set_debug_mode() {
-    local filtered_args=()
-    local debug_mode=false
-    
-    for arg in "$@"; do
-        case "$arg" in
-            --debug)
-                debug_mode=true
-                ;;
-            *)
-                filtered_args+=("$arg")
-                ;;
-        esac
-    done
-    
-    if [ "$debug_mode" = true ]; then
-        export KUGETSU_VERBOSITY="debug"
-        echo "[DEBUG] Debug mode enabled" >&2
-    fi
-    
-    echo "${filtered_args[@]}"
-}
-
 cmd_continue() {
     local session_name=""
     local message=""
@@ -421,7 +398,7 @@ cmd_continue() {
         if [ -z "$session_name" ]; then
             session_name="$arg"
         else
-            message="$arg"
+            message="${message}${message:+ }${arg}"
         fi
     done