fix: scope preserve_thinking to tool-call turns, remove extra newline in continuation turns

chat_template.jinja

@@ -362,7 +362,6 @@
         {%- if ns.prev_message_type == 'tool_call' and not ns_tr_out.flag -%}
             {{- '<|tool_response>' -}}
         {%- elif continues_into_next -%}
-            {{- '\n' -}}
         {%- elif not (ns_tr_out.flag and not has_content) -%}
             {{- '<turn|>\n' -}}
         {%- endif -%}