Taskbar: 7 weapon sets and 7 combat-art slots

cUI_Taskbar2's slot arrays move behind the (enlarged) object with room
for 7 each; all instructions addressing them, the relative accesses
between the two arrays, the slot loops and the count clamp are patched
from tables in game/addresses.h (belt loops untouched). Slots 6 / 7
unlock at levels 45 / 65; AssignArtToSlot accepts slots up to 6. Slot
keys call the taskbar's selection directly (honouring COMBINE_SLOTS).

Shared code: re::PatchAll / PatchInstructionByte for patch tables,
game/engine/objects.h for object, RTTI and kernel calls, slot-hook
templates in skillslots.cpp.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

CMakeLists.txt

@@ -39,6 +39,7 @@ add_library(sacred_re SHARED
     src/mods/input.cpp
     src/mods/skillslots.cpp
     src/mods/inventory_save.cpp
+    src/mods/skillbar.cpp
 )
 target_include_directories(sacred_re PRIVATE src)
 target_compile_options(sacred_re PRIVATE ${SACRED_RE_CXX_FLAGS})