refactor(cw)!: replace legacy CW engine with DeepCW in both entry points

DeepCW 成为唯一 CW 解码内核, 不保留旧引擎作兜底 (用户决定: 完全移植)。

删除旧内核 (1298 行):
- CwDecoder.kt / CwBayesianDecoder.kt / CwChannelTracker.kt / CwSpectrogram.kt
- CwDsp / CwFFT / CwSTFFT / CwGoertzel / CwFilter / CwResampler.kt
- CwDecoderTest.kt
旧内核的自动定频与 squelch 门控由 DeepCW 的 400-1200Hz 固定频窗替代 ——
模型自带定频, 不再需要频谱峰值跟踪和噪声门。

两个 CW 入口都改接 DeepCW:
1. feature:cw 独立整页 CwDecodeScreen.kt 重写为纯 Compose (瀑布图 -> 实时行
   -> 历史区), 移除 AndroidView/LayoutInflater 和被删的 activity_main 布局;
   删除 CwSettingsDialog.kt (旧引擎的手动音调/带宽面板, DeepCW 全自动无需)
2. feature:radar 内嵌可折叠面板改走 ViewModel 的 CW state/action, 移除
   Morse Expert 控制器与 cw_panel_main 布局
   (该面板此前注释写明 "no longer feeds it", ViewModel 里的 CW 通路是死代码)

新增 CwWaterfall.kt: 复用 CwDeepSpectrogram 绘制瀑布图, 显示的正是模型
分析的 400-1200Hz 频段与同一批幅值。

接口接线:
- IMainContainer.provideCwDecoder() 提供 ICwDecoder (实现需 Context 读 assets)
- RadarViewModel 构造新增 cwDecoderFactory, onCleared() 中 close() 释放
  OrtSession 避免原生内存泄漏
- 删除已无调用方的 RadarAction.CwSetToneFreq (DeepCW 定频固定, 无参数可调);
  CwSubState.cwToneFreq 语义改为只读显示检测到的音调

依赖清理:
- feature:radar 不再依赖 feature:cw 与 constraintlayout
- feature:cw 不再依赖 constraintlayout

字符串: feature:cw 清理 Morse Expert 遗留串 (premium/rate/help/
tap_back_again_to_close/purple_500), 按 en/zh/tr/in/id 五语补全新串;
core:presentation 补 radar_cw_tone / radar_cw_waiting 五语。

验证:
./gradlew :core:domain:test => 4 个测试类全绿
./gradlew :feature:cw:compileDebugKotlin => BUILD SUCCESSFUL
./gradlew :feature:radar:compileDebugKotlin => BUILD SUCCESSFUL
./gradlew :core:data:compileDebugKotlin => BUILD SUCCESSFUL

core/presentation/src/main/res/values-id/strings.xml

@@ -132,6 +132,8 @@
     <string name="radar_cw_start">Mulai</string>
     <string name="radar_cw_stop">Berhenti</string>
     <string name="radar_cw_reset">Bersihkan</string>
+    <string name="radar_cw_tone">Nada %1$d Hz</string>
+    <string name="radar_cw_waiting">Menunggu sinyal…</string>
     <string name="map_prev">Sebelumnya</string>
     <string name="map_next">Berikutnya</string>
     <string name="map_copyright" translatable="false">© Kontributor OpenStreetMap</string>

core/presentation/src/main/res/values-in/strings.xml

@@ -131,6 +131,8 @@
     <string name="radar_cw_start">Mulai</string>
     <string name="radar_cw_stop">Berhenti</string>
     <string name="radar_cw_reset">Bersihkan</string>
+    <string name="radar_cw_tone">Nada %1$d Hz</string>
+    <string name="radar_cw_waiting">Menunggu sinyal…</string>
     <string name="map_prev">Sebelumnya</string>
     <string name="map_next">Berikutnya</string>
     <string name="map_copyright" translatable="false">© Kontributor OpenStreetMap</string>

core/presentation/src/main/res/values-tr/strings.xml

@@ -296,5 +296,7 @@
         \n• BA7OPF (pass matching feature)
         \n• BG7NTA</string>
     <string name="prefs_outro_license">Bu uygulama herhangi bir garanti sunmaz</string>
+    <string name="radar_cw_tone">Ton %1$d Hz</string>
+    <string name="radar_cw_waiting">Sinyal bekleniyor…</string>
 
 </resources>

core/presentation/src/main/res/values-zh/strings.xml

@@ -123,6 +123,8 @@
     <string name="radar_cw_start">开始</string>
     <string name="radar_cw_stop">停止</string>
     <string name="radar_cw_reset">清空</string>
+    <string name="radar_cw_tone">音调 %1$d Hz</string>
+    <string name="radar_cw_waiting">等待信号…</string>
 
     <!-- Map screen -->
     <string name="map_prev">上一个</string>

core/presentation/src/main/res/values/strings.xml

@@ -141,6 +141,8 @@
     <string name="radar_cw_start">Start</string>
     <string name="radar_cw_stop">Stop</string>
     <string name="radar_cw_reset">Clear</string>
+    <string name="radar_cw_tone">Tone %1$d Hz</string>
+    <string name="radar_cw_waiting">Waiting for signal…</string>
 
     <!-- Map screen -->
     <string name="map_prev">Prev</string>