speed20: boost固定26 + Z_COOLDOWN定速16

src/camera.cpp

@@ -1031,13 +1031,13 @@ static void motor_update(bool zebra_block, bool tl_block)
     prev_zstate = g_zstate;
     prev_tlstate = g_tl_state;
 
-    double spd = target_speed * boost_factor();
-
-    // 斑马线起步后 3.3~5s 降速走稳
-    if (g_zstate == Z_COOLDOWN) {
-        time_t elapsed = time(nullptr) - g_ztime;
-        if (elapsed >= 3.3 && elapsed < 5)
-            spd = std::min(spd, 13.0);
+    double spd;
+    if (boost_factor() > 1.0) {
+        spd = 26.0;                           // 起步弹射
+    } else if (g_zstate == Z_COOLDOWN) {
+        spd = 16.0;                           // 冷却期定速
+    } else {
+        spd = target_speed;                   // 正常行驶
     }
 
     // 弯道减速: 舵机偏差越大 → 速度越低