update decomp.bat in accordance to project directory changes + bugfix (#243)

* ObjectFileDB: Fix crash if obj list text has no objects

* rename "decomp.bat" to "decomp-jak1.bat"

decomp-jak1.bat

@@ -1,7 +1,7 @@
 @echo off
 :: The caret ^ acts as a line break but does not make the next line a different command.
-out\build\Release\bin\decompiler decompiler\config\jak1_ntsc_black_label.jsonc iso_data ^
-decompiler_out
+out\build\Release\bin\decompiler decompiler\config\jak1_ntsc_black_label.jsonc iso_data\jak1 ^
+decompiler_out\jak1
 :: The pause command makes the batch operation halt with a "Press any key to continue..." message.
 :: Useful for example if the decompiler failed and exited for whatever reason, or for verifying its
 :: success.

decompiler/ObjectFile/ObjectFileDB.cpp

@@ -417,8 +417,10 @@ std::string ObjectFileDB::generate_obj_listing() {
     assert(int(all_unique_names.size()) == unique_count);
   }
 
-  result.pop_back();  // kill last new line
-  result.pop_back();  // kill last comma
+  if (result.length() >= 2) {
+    result.pop_back();  // kill last new line
+    result.pop_back();  // kill last comma
+  }
   return result + "]";
 }