"FreedroidRPG 1.0rc1 encountered a problem in function: find_free_floor_index
The item array for level 0 was full."

Steps to reproduce:
0. unzip and load attached savegame "Sari"
1. Teleport via "protecting zone" to town
2. Drop one police shield to floor
3. Dropping next shield will not working
4. in the inventory swap the attached helmet with the worker helmet of inventory
5. application will crash

expected behavior:
- error message dropping item to floor
- working helmet switch

discovered behavior:
- not working drop item, no error message
- application crash on helmet change

reproduceable also in FreedroidRPG 1.0rc2

Position to add status message e.g. "There is not enough space on the ground." on item drop: https://gitlab.com/freedroid/freedroid-src/-/blob/master/src/items.c#L1204

No idea what the helmet switch has to do with it.

When you try switching the item, it forces the placement of the item on the 
floor. If there is no more space to drop items, it silently explodes (not even 
a traceback O.o)


The guilt is items.c:590, function "MakeHeldFloorItemOutOf".
It calls Terminate(EXIT_FAILURE), so not traceback is produced.


Review Request 2402 will get rid of both DebugPrintf and Terminate in favor of 
error_message(IS_FATAL).

The ideal behavior, however, would be canceling the operation, reason why I 
assing this to fluzz and raise priority to "important". (Why not critical if it 
is a crash, again? Meh, nevermind.)

commit 9937c9cae replaces the static C array by a dynarray.

this fixes the reported issues