Improve auto-staging on launch to work with more ships.

Wait until ship fully loaded (unpacked) before commencing boot procedure.

boot/default.ks

@@ -1,5 +1,6 @@
 CLEARSCREEN.
 print "=================== BOOTING ===================".
+wait until SHIP:UNPACKED.
 
 if HOMECONNECTION:ISCONNECTED {
     update_scripts().

launch.ks

@@ -47,14 +47,16 @@ function launch {
     set NAVMODE to "SURFACE".
     lock STEERING to HEADING(launch_azimuth, 90).  // roll to launch azimuth
     lock THROTTLE to 1.0.
-    STAGE.
     
-    // Enable auto-stage when the maximum engine thrust changes (i.e. some engines ran out of fuel)
-    on SHIP:MAXTHRUSTAT(0) {
-        when STAGE:READY then {
-            print "STAGING".
-            STAGE.
-        }.
+    
+    // LAUNCH
+    
+    // Can't use flameout or MAXTHRUSTAT on the initial staging, since the rocket may be held down by a launch tower
+    until STAGE:SOLIDFUEL + STAGE:LIQUIDFUEL <> 0 stage_when_ready().
+    
+    // Auto-stage when any of the engines flameout or if there are no active engines (e.g. when we have an intermediate stage for decouplers before activating the next engine)
+    when any_flameout() or SHIP:MAXTHRUSTAT(0) = 0 then {
+        stage_when_ready().
         return true.  // preserve trigger
     }
 

util.ks

@@ -11,6 +11,12 @@ function warp_for {
 }
 
 
+function stage_when_ready {
+    wait until STAGE:READY.
+    print "STAGING".
+    STAGE.
+}
+
 
 function isp_sum {
     local sum is 0.
@@ -22,6 +28,15 @@ function isp_sum {
 }
 
 
+function any_flameout {
+    list ENGINES in engines_list.
+    for engine in engines_list {
+        if engine:FLAMEOUT return true.
+    }
+    return false.
+}
+
+
 function round_towards_zero {
     parameter n.