fix(ncm §33): 流媒专项批六项——流式SIGSEGV防御日志/档位保真(无损级必须flac+显示档按实际)/封面4xx不重试/收藏显隐/缓存命名迁移/topbar位图图标

- §2① ncm_api.c level_attempt: 无损级(hires/lossless及以上)命中必须 type=flac，返回 mp3 视为该档不可用续降
  (修「hires 档静默给 mp3 被当命中」)
- §2② player_manager.c eff_level_for_resp: 显示档按响应实际格式/码率——mp3 绝不显示 Hi-Res(≤128k→标准, 否则极高),
  flac 采信链 eff; br 未知钳 ≤EXHIGH
- §1 流式 SIGSEGV(《十面埋伏》sig=11) 审计+UBSAN 探针未复现 → 落地防御日志(dl start/done/interrupt + play done fin/exp/fail/underrun)
- §3 cover.c: download_cover 回填 rc/status; 确定性 4xx(404等)不重试立即跳下一张, 仅瞬时错误退避(rc=%d status=%d 日志)
- §4 playlist.c: pl_show_fav 我创建(is_collected==0)隐藏收藏钮, 我收藏保留, 搜索歌单保守显示(评论槽并入无空洞)
- §5 ncm_cache.c 双点→单点迁移 + player_manager song_local_file 旧键→当前档位键(不重下)
- §6 home.c: topbar 动作 ⚙↻⌕ 迁移 sb_icons 位图(meow_topappbar_set_item_icon, 修 4k 字库豆腐)
- 测试: test_ncm_core 新 test_grade_flac_gate + test_cache 双点迁移断言; degrade_sim/player_flow_sim 桩 flac 化
- 验证: stream/player_flow/window/search/cache_evict/degrade sim 全 PASS + test_ncm_core host+mipsel(qemu) + mem_sim + build_ncm.sh 0 warning
- 新 ncm md5 cb818786 (text 1017110/bss 1362500), 未部署留主会话; 0 真实 NCM 业务请求

patch_v2/ncm_app/bench/degrade_sim.c

@@ -41,7 +41,12 @@ static int fake_try(const char *dev, const char *ck, const char *id, int level,
     if (level > g_avail_from) return NCM_OK;   /* 该档不可用：url 空 */
     snprintf(out->url, sizeof out->url, "http://sim/%lld.%s", (long long)12345,
              (level >= NCM_LEVEL_LOSSLESS) ? "flac" : "mp3");
-    snprintf(out->type, sizeof out->type, "%s", g_type);
+    /* §2① 档位保真：无损级及以上，服务端 encodeType=flac → 应答 type=flac（真实）；g_type=""
+     * （缺失）时保留空串，交给 level_attempt 按 url 扩展名推断（测试该推断路径）。 */
+    if (level >= NCM_LEVEL_LOSSLESS && g_type[0])
+        snprintf(out->type, sizeof out->type, "flac");
+    else
+        snprintf(out->type, sizeof out->type, "%s", g_type);
     if (g_resp_level) snprintf(out->level, sizeof out->level, "%s", g_resp_level);
     out->br = 320000;
     out->size = 9000000;

patch_v2/ncm_app/bench/player_flow_sim.c

@@ -150,6 +150,14 @@ int ncm_cache_open_resume(const ncm_cache_t *c, const char *id, const char *ext,
 }
 int ncm_cache_part_remove(const ncm_cache_t *c, const char *id, const char *ext)
 { (void)c; (void)id; (void)ext; g_part_removes++; g_part_size = 0; return NCM_OK; }
+/* §NEW 任务5：song_local_file 旧键迁移调 ncm_cache_path（本 sim 走 stub 缓存）；仅链接用。 */
+int ncm_cache_path(const ncm_cache_t *c, const char *id, const char *ext, char *out, size_t out_sz)
+{
+    const char *e = ext; if (e && e[0] == '.') e++;
+    snprintf(out, out_sz, "%s/song_%s.%s",
+             (c && c->dir[0]) ? c->dir : "/tmp", id ? id : "", e ? e : "bin");
+    return NCM_OK;
+}
 
 int ncm_api_song_url_auto(const char *dev, const char *ck, const char *id, int level,
                           ncm_play_url_t *out, int *out_level)
@@ -434,12 +442,14 @@ int main(void)
     }
     g_eof = 0; g_reads_left = -1;   /* 上一步非 VIP 部分设了 g_eof=1 让 song0 收尾；SVIP song1 需正常播 */
     g_vip = NCM_VIP_SVIP; g_cache_ok = 0; g_url_calls = 0; g_url_req_level = -1;
+    g_url_type = "flac";            /* §2②：SURROUND 为无损级 → 应答 flac（真实），eff 回填 SURROUND */
     player_manager_play(1);
     CHECK(wait_state(NCM_PC_PLAYING, 3000), "svip song playing");
     CHECK(g_url_req_level == NCM_LEVEL_SURROUND,
           "req level=%d (expect SURROUND=%d：SVIP 不钳顶)", g_url_req_level, NCM_LEVEL_SURROUND);
     CHECK(player_manager_eff_level() == NCM_LEVEL_SURROUND,
           "eff_level=%d (expect SURROUND)", player_manager_eff_level());
+    g_url_type = "mp3";
     g_eof = 1;
 
     printf("== P8: fee 门禁（§20：fee∈{1,4} 且非会员 → NCM_ERR_VIP，不发 song_url）==\n");