v2收尾：手势升级 + 暂停退出 + 结局语音化 + 分支补全 + 12条新音频

gestures.js: 新增长按(1s)、两指长按(暂停)、三指点击(退出)，支持多指检测
engine.js: REPLY_COUNT变量、长按重播/状态广播、暂停恢复退出机制、
  选择提示音、结局台词预录音频替换TTS、内容预警+心理热线
story.js: MSG-10/11 follow-up补全down(沉默)选项
index.html: 操作指南添加长按/安全手势、内容预警文字
batch_tts_voxcpm.py: 新增12条台词(结局旁白+系统提示+分支NPC反应)
audio/mp3/tts: 12个VoxCPM2生成的林夏声线MP3

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

game/js/story.js

@@ -388,6 +388,11 @@ const MESSAGES = [
               linxia: lx('v2_msg10_rw_linxia_curious_wav_v1.mp3'),
               npcReact: [rx('v2_msg10_rw_react_curious_wav_v1.mp3')],
             },
+            down: {
+              isSilence: true,
+              npcReact: [rx('v2_msg10_rw_react_silent_wav_v1.mp3')],
+              profile: { avoidance: 1 },
+            },
           },
         },
       },
@@ -415,7 +420,8 @@ const MESSAGES = [
             },
             down: {
               isSilence: true,
-              npcReact: [rx('v2_msg10_call_react_silent_wav_v1.mp3')],
+              npcReact: [rx('v2_msg10_call_react_down_wav_v1.mp3')],
+              profile: { avoidance: 1 },
             },
           },
         },
@@ -469,6 +475,12 @@ const MESSAGES = [
               npcReact: [rx('v2_msg11_react_cold_wav_v1.mp3')],
               state: { HE_BACK: false },
             },
+            down: {
+              isSilence: true,
+              npcReact: [rx('v2_msg11_r3_react_silent_wav_v1.mp3')],
+              state: { HE_BACK: false },
+              profile: { avoidance: 1 },
+            },
           },
         },
       },