fix-unit-occupancy, autogems: stop running while embarking

Related to #1286 fix

docs/changelog.txt

@@ -45,6 +45,7 @@ changelog.txt uses a syntax similar to RST, with a few special sequences:
 - Fixed many tools passing incorrect arguments to printf-style functions, including a few possible crashes (`changelayer`, `follow`, `forceequip`, `generated-creature-renamer`)
 - Fixed ``-g`` flag (GDB) in Linux ``dfhack`` script (particularly on x64)
 - `autochop`, `autodump`, `autogems`, `automelt`, `autotrade`, `buildingplan`, `dwarfmonitor`, `fix-unit-occupancy`, `fortplan`, `stockflow`: fix issues with periodic tasks not working for some time after save/load cycles
+- `autogems`, `fix-unit-occupancy`: stopped running when a fort isn't loaded (e.g. while embarking)
 - `buildingplan`, `fortplan`: stop running before a world has fully loaded
 - `autogems`:
     - stop running repeatedly when paused

plugins/autogems.cpp

@@ -222,7 +222,8 @@ void create_jobs() {
 }
 
 DFhackCExport command_result plugin_onupdate(color_ostream &out) {
-    if (running && !World::ReadPauseState() && (world->frame_counter % DELTA_TICKS == 0)) {
+    if (running && !World::ReadPauseState() && Maps::IsValid() &&
+            (world->frame_counter % DELTA_TICKS == 0)) {
         create_jobs();
     }
 

plugins/fix-unit-occupancy.cpp

@@ -211,7 +211,7 @@ DFhackCExport command_result plugin_enable (color_ostream &out, bool enable)
 
 DFhackCExport command_result plugin_onupdate (color_ostream &out)
 {
-    if (is_enabled && World::isFortressMode())
+    if (is_enabled && World::isFortressMode() && Maps::IsValid())
     {
         if (world->frame_counter % run_interval == 0 && !World::ReadPauseState())
         {