feat(ncm): 风控加固——接口响应短 TTL 缓存 + 游客 MUSIC_A + track/all 死代码

三（按 NCMAPI_NOTES §2.1/§4/§6）：
① 接口级响应缓存（对齐参考 apicache 2 分钟，防风控高频 ip 错误）：
   - 新增 core/ncm_apicache.{c,h}——内存 4 槽 LRU（单槽≤128KB，TTL 120s，
     键=md5(path+\x01+json)）+ 可选盘缓存 <data_dir>/ncm_api_cache/.json
     （8B 墙钟头+body，超 TTL miss 并删，30s 节流清过期）。自包含模块
     （仅 libc+pthread+clock_gettime），可独立链接无符号冲突。
   - ncm_api.c：api_post 拆「请求+解析」两段，新增 api_post_cached；四个只读
     接口接线：user_playlist/playlist_detail/song_detail/cloudsearch。
     song_url/lyric/vip 不入缓存。
   - 手动刷新绕过：ncm_api_cache_refresh_path(path) 一次性标记；home/歌单
     topbar ↻ 接入；playlist_open/search 不标记（走缓存）。
   - 盘层挂载 appstate_init；登出 appstate_logout 全清（防串账号）。
② 游客 MUSIC_A：ncm_req.c weapi+eapi 无 MUSIC_U 且非 login 路径补
   MUSIC_A=anonymous_token（对齐参考 cookie 伪装）。
③ track/all 死代码清理：移除 ncm_api_playlist_track_all（真实服务器 8 形态全
   404，无调用点）；ncm_api_parse_track_all 保留（离线重放/单测），注释标注
   「已验证不存在，勿用于真实请求」。

验证：新 bench/apicache_sim.c（0 网络）①TTL 内不重复请求/②过期重拉/③手动
刷新绕过/④cloudsearch 按键区分/⑤清空重拉/⑥盘缓存写入+clear 全 PASS；stream/
player_flow/window/search/cache_evict(1-9)/pagination/playlist_race sim 全
PASS；test_ncm_core host+mipsel(qemu) PASS；build_ncm.sh -Wall -Wextra 0
warning（text 1026914/data 1664/bss 1363460）；0 高频真实请求。新 ncm md5
a69c93538920eba9d42a2ebb42f8fdca（留主会话上卡）。

patch_v2/ncm_app/bench/apicache_sim.c

@@ -0,0 +1,132 @@
+/* bench/apicache_sim.c — 接口级响应短 TTL 缓存验证（风控加固 §1，0 真实 NCM 请求）。
+ *
+ * 用**真实** core（ncm_api.c / ncm_req.c / ncm_crypto.c / ncm_json.c / ncm_common.c /
+ * ncm_apicache.c），仅把网络层 ncm_http_request 换成计数桩（canned JSON 响应），验证：
+ *   ① TTL 内重复调用不重复请求（缓存命中）；
+ *   ② TTL 过期后重拉（expired re-fetch）；
+ *   ③ 手动刷新（ncm_api_cache_refresh_path）绕过缓存；
+ *   ④ cloudsearch 缓存按键（关键词/分页）区分，不同关键词各拉一次；
+ *   ⑤ 清空（登出）后重拉；
+ *   ⑥ 盘缓存写入/清除（文件存在性）。
+ * 风控纪律：0 次真实 NCM 请求（网络层计数桩）；sleep 仅用于 TTL 过期（短 TTL=1s）。
+ *
+ * 编译（宿主），在 ncm_app 目录：见 build_ncm_sims.sh 新增 apicache_sim 段。
+ * 运行：./apicache_sim
+ */
+#include "ncm.h"
+#include "ncm_http.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+static int g_http_calls = 0;      /* ncm_http_request 桩计数 = 真实网络调用数 */
+
+/* 桩：不联网，按 url 返回 canned JSON，并计数。 */
+static const char *BODY_USER_PL   =
+    "{\"code\":200,\"playlist\":[{\"id\":\"1\",\"name\":\"P1\",\"coverImgUrl\":\"http://x/c.jpg\",\"trackCount\":3,\"subscribed\":false}]}";
+static const char *BODY_CLOUD_SEARCH =
+    "{\"code\":200,\"result\":{\"songCount\":1,\"songs\":[{\"id\":\"100\",\"name\":\"S\",\"dt\":200000,\"fee\":0,"
+    "\"ar\":[{\"name\":\"A1\"}],\"al\":{\"name\":\"AL1\",\"picUrl\":\"http://x/1.jpg\"}}]}}";
+
+int ncm_http_request(const ncm_http_req_t *req, char *buf, size_t buf_sz, ncm_http_resp_t *resp) {
+    (void)req; (void)buf_sz;
+    g_http_calls++;
+    const char *body = (strstr(req->url, "cloudsearch") != NULL) ? BODY_CLOUD_SEARCH : BODY_USER_PL;
+    size_t n = strlen(body);
+    memcpy(buf, body, n);
+    memset(resp, 0, sizeof *resp);
+    resp->status = 200;
+    resp->body = buf;
+    resp->body_len = n;
+    resp->content_length = n;
+    return NCM_OK;
+}
+void ncm_http_set_verify_default(int verify, const char *ca_path) { (void)verify; (void)ca_path; }
+
+static int g_fail = 0;
+#define CHECK(cond, fmt, ...) do { \
+    if (cond) printf("  PASS  " fmt "\n", ##__VA_ARGS__); \
+    else { printf("  FAIL  " fmt "\n", ##__VA_ARGS__); g_fail = 1; } \
+} while (0)
+
+static const char *g_device = "AA11BB22CC33DD44EE55FF6600112233445566778899AABB00";
+
+int main(void) {
+    ncm_apicache_init(NULL);              /* 内存缓存；盘层本轮单独测（临时目录） */
+    ncm_apicache_ttl_set(NCM_APICACHE_TTL_S);
+
+    ncm_playlist_t pls[8]; int pn = 0;
+
+    /* ① TTL 内不重复请求（user/playlist） */
+    int c0 = g_http_calls;
+    int rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(rc == NCM_OK && pn == 1, "user_playlist rc=%d n=%d (first = real)", rc, pn);
+    rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(g_http_calls == c0 + 1, "TTL 内不重复请求: calls=%d (期望 %d)", g_http_calls, c0 + 1);
+    CHECK(rc == NCM_OK && pn == 1, "cached user_playlist rc=%d n=%d", rc, pn);
+
+    /* ② TTL 过期后重拉（短 TTL=1s；sleep 2s 确保严格超 1000ms 触发过期） */
+    ncm_apicache_ttl_set(1);
+    sleep(2);                              /* 等上一条（默认 120s 存的）过期 */
+    c0 = g_http_calls;
+    rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(g_http_calls == c0 + 1, "过期重拉: calls=%d (期望 +1)", g_http_calls);
+    CHECK(rc == NCM_OK && pn == 1, "refetch after expiry rc=%d n=%d", rc, pn);
+    /* 刚存了 1s TTL 的新条目，立即再取应命中 */
+    int c1 = g_http_calls;
+    rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(g_http_calls == c1, "重拉后 TTL 内命中: calls=%d (期望不增)", g_http_calls);
+    ncm_apicache_ttl_set(NCM_APICACHE_TTL_S);   /* 还原默认 TTL */
+
+    /* ③ 手动刷新绕过缓存（一次性消费） */
+    c0 = g_http_calls;
+    ncm_api_cache_refresh_path("/api/user/playlist");
+    rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(g_http_calls == c0 + 1, "手动刷新绕过: calls=%d (期望 +1)", g_http_calls);
+    CHECK(rc == NCM_OK && pn == 1, "refresh bypass rc=%d n=%d", rc, pn);
+    c1 = g_http_calls;
+    rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(g_http_calls == c1, "刷新后（路径已消费）回缓存: calls=%d", g_http_calls);
+
+    /* ④ cloudsearch 缓存：同关键词命中、不同关键词各自请求 */
+    ncm_song_t songs[8]; int sn = 0; int64_t total = -1;
+    c0 = g_http_calls;
+    rc = ncm_api_cloudsearch_song(g_device, "", "abc", 0, 30, songs, 8, &sn, &total);
+    CHECK(rc == NCM_OK && sn == 1, "cloudsearch abc rc=%d n=%d", rc, sn);
+    int c2 = g_http_calls;
+    rc = ncm_api_cloudsearch_song(g_device, "", "abc", 0, 30, songs, 8, &sn, &total);
+    CHECK(g_http_calls == c2, "cloudsearch 同关键词命中: calls=%d", g_http_calls);
+    rc = ncm_api_cloudsearch_song(g_device, "", "def", 0, 30, songs, 8, &sn, &total);
+    CHECK(g_http_calls == c2 + 1, "cloudsearch 不同关键词各拉一次: calls=%d (期望 %d)", g_http_calls, c2 + 1);
+    CHECK(rc == NCM_OK && sn == 1, "cloudsearch def rc=%d n=%d", rc, sn);
+
+    /* ⑤ 清空（登出/换账号）后重拉 */
+    c0 = g_http_calls;
+    ncm_apicache_clear();
+    rc = ncm_api_user_playlist(g_device, "", "0", 30, 0, pls, 8, &pn);
+    CHECK(g_http_calls == c0 + 1, "清空后重拉: calls=%d (期望 +1)", g_http_calls);
+
+    /* ⑥ 盘缓存写入/清除（临时目录，默认 TTL） */
+    char tmpdir[128];
+    snprintf(tmpdir, sizeof tmpdir, "/tmp/apicache_sim_%ld", (long)getpid());
+    mkdir(tmpdir, 0777);
+    ncm_apicache_init(tmpdir);
+    ncm_apicache_ttl_set(NCM_APICACHE_TTL_S);
+    ncm_apicache_put("0123456789abcdef0123456789abcdef", "hello-disk", 10);
+    char dp[512];
+    snprintf(dp, sizeof dp, "%s/ncm_api_cache/0123456789abcdef0123456789abcdef.json", tmpdir);
+    struct stat st;
+    CHECK(stat(dp, &st) == 0, "盘缓存写入文件存在: %s", dp);
+    /* 命中盘缓存（内存若也存了会先命中内存；这里单独验证 clear 后文件被删） */
+    ncm_apicache_clear();
+    CHECK(stat(dp, &st) != 0, "盘缓存 clear 后文件删除");
+    /* 清掉临时目录（内容已由 clear 删除，rmdir） */
+    char cmd[160];
+    snprintf(cmd, sizeof cmd, "rm -rf \"%s\"", tmpdir);
+    if (system(cmd) != 0) { /* 忽略 */ }
+
+    printf("\n%s\n", g_fail ? "RESULT: FAIL" : "RESULT: PASS");
+    return g_fail ? 1 : 0;
+}