feat(kugetsu): add --debug flag for real-time output capture

- Add --debug flag to start/resume for verbose opencode output
- Capture debug logs to ~/.kugetsu/sessions/<id>/debug.log
- Add --debug to stop/destroy for viewing logs before actions
- Position-agnostic flag parsing (--debug can appear anywhere)

skills/kugetsu/scripts/kugetsu

@@ -190,7 +190,7 @@ cmd_start() {
     
     echo "Starting session '$session_id'..."
     if [ "$DEBUG_MODE" = true ]; then
-        stdbuf -oL opencode run --print-logs --log-level DEBUG --session "$session_id" "$message" 2>&1 | tee "$session_dir/debug.log"
+        opencode run --print-logs --log-level DEBUG --session "$session_id" "$message" 2>&1 | tee "$session_dir/debug.log"
     else
         opencode run --session "$session_id" "$message"
     fi
@@ -321,7 +321,7 @@ cmd_resume() {
     
     echo "Resuming session '$session_id'..."
     if [ "$DEBUG_MODE" = true ]; then
-        stdbuf -oL opencode run --print-logs --log-level DEBUG --continue --session "$session_id" "$message" 2>&1 | tee "$session_dir/debug.log"
+        opencode run --print-logs --log-level DEBUG --continue --session "$session_id" "$message" 2>&1 | tee "$session_dir/debug.log"
     else
         opencode run --continue --session "$session_id" "$message"
     fi