Read client signed int32 fields as signed

Add ResStream.read_long/write_long and use them for every CObjects
field the client loads with ResStream_ReadInt32 (sb.exe 0x7E1700)
as a value: rank info, attribute/skill/resource amounts, requirements,
door/deed/container/key fields, natural attacks, hardpoints, sound
event types and sparse VAL_LONG (LoadSaveBehavior<long>). Hash/enum
fields, list counts and flag words keep unsigned reads.

The binary is unchanged; JSON now shows e.g. -1 instead of 4294967295
(rank_hirelings, rank_rank) and -10 instead of 4294967286 (attr_adj).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

mbEditorPro2.0/arcane/objects/common/SparseData.py

@@ -23,7 +23,7 @@ class SparseData:
             value = None
 
             if sparse_type == SPARSE_VAL_LONG:
-                value = stream.read_dword()
+                value = stream.read_long()
 
             elif sparse_type == SPARSE_VAL_FLOAT:
                 value = stream.read_float()
@@ -65,7 +65,7 @@ class SparseData:
 
             sparse_type = SPARSE_TAG_TO_SPARSE_TYPE[tag]
             if sparse_type == SPARSE_VAL_LONG:
-                stream.write_dword(value)
+                stream.write_long(value)
 
             elif sparse_type == SPARSE_VAL_FLOAT:
                 stream.write_float(value)