feat(ui): M6.38批 — P1 MD3细化(SDK对话框28)+批②底部上滑回桌面+批6 ncm顶栏回播放页+批④面板后台列表+launcher UI微调(歌词页黑半透明底/播放页布局下移)+封面空artwork保留修复

- P1: meow_ui_dialog.c 对话框底框 radius_card→MEOW_SHAPE_EXTRA_LARGE(28) 三处(:103填充/:104描边/:361 BottomSheet); meow_ui_widgets.h 新增 MEOW_SHAPE_EXTRA_LARGE 28 宏; TextField/FAB/Slider/Progress 按设计文档保留
- 批②: np_gesture.h 新增 NP_GEST_HOME+np_home_gesture(底部热区上滑,与左缘返回对称互斥); now_playing.c 新增 np_draw_home_bar(屏底左缘pill指示条)+手势衔接; test_now_playing_widgets G5b
- 批6: ncm home.c 顶栏加回播放页按钮(MEOW_ICON_QUEUE_MUSIC)→push(ACT_PLAYER), 无音频也生效
- 批④: meowpanel /api/ams/bg 只读端点+前端后台列表页+杀/清复用kill通道
- UI微调: now_playing.c 播放页布局宏下移(NP_COVER_Y 84/NP_BTN_Y 612消底部留白)+歌词页背景统一黑色半透明叠层(弃封面取色底,删 np_draw_lyric_coverbg)
- 封面保留: now_playing.c/notif_center.c 空artwork保留上一张已解码封面(防暂停/开歌单致META报空artwork后封面闪没); test_np_cover C2断言更新+mirror同步

0warning;宿主测试 test_np_cover ALL PASS;launcher/ncm/panel 宿主测试无回归。二进制留批量批次未入库

patch_v2/sdk/meow_ui_dialog.c

@@ -100,8 +100,8 @@ static void dlg_calc(meow_dialog *d, const meow_theme *th, dlg_geom *g)
 static void dlg_card(meow_dialog *d, const meow_theme *th, const dlg_geom *g)
 {
     int pad = 24;
-    meow_gfx_fill_round(g->dx, g->dy, g->dw, g->dh, th->radius_card, th->surfaceContainerHighest);
-    meow_ui_draw_rect_round(g->dx, g->dy, g->dw, g->dh, th->radius_card, th->outline);
+    meow_gfx_fill_round(g->dx, g->dy, g->dw, g->dh, MEOW_SHAPE_EXTRA_LARGE, th->surfaceContainerHighest);
+    meow_ui_draw_rect_round(g->dx, g->dy, g->dw, g->dh, MEOW_SHAPE_EXTRA_LARGE, th->outline);
     meow_ui_text(g->dx + pad, g->dy + pad, d->title, th->font_title, th->onSurface);
 
     if (d->type == MEOW_DLG_SELECT) {
@@ -358,7 +358,7 @@ int meow_sheet_open(meow_sheet *s)
     meow_ui_modal_capture();             /* M2.71-bug3：拍下背景，关闭即还原（scrim 只叠一层/无残影） */
     /* 首次绘制：遮罩 + 底部面板（顶部圆角） */
     meow_ui_fill_rect_alpha(0, 0, W, H, 0x000000, 150);
-    meow_gfx_fill_round(0, py, W, ph, th->radius_card, th->surfaceContainerHighest);
+    meow_gfx_fill_round(0, py, W, ph, MEOW_SHAPE_EXTRA_LARGE, th->surfaceContainerHighest);
     meow_ui_text(pad, py + pad, s->title, th->font_title, th->onSurface);
     for (int i = 0; i < s->nitems; i++) {
         int ry = py + pad + meow_ui_text_height(th->font_title) + 12 + i * MEOW_MODAL_ROW;