Build Problem: any.hpp missing

## Bug Report

### Build Problem

```
In file included from ./OpenTimelineIO/src/opentimelineio/anyDictionary.h:6,
from ./OpenTimelineIO/src/opentimelineio/serializableObject.h:9,
from ./OpenTimelineIO/src/opentimelineio/serializableObjectWithMetadata.h:6,
from ./OpenTimelineIO/src/opentimelineio/composable.h:6,
from ./OpenTimelineIO/src/opentimelineio/item.h:7,
from ./OpenTimelineIO/src/opentimelineio/clip.h:6,
from ./OpenTimelineIO/src/opentimelineio/clip.cpp:4:
./OpenTimelineIO/src/opentimelineio/any.h:6:10: fatal error: any/any.hpp: No such file or directory
6 | #include "any/any.hpp"
| ^~~~~~~~~~~~~
compilation terminated.
In file included from ./OpenTimelineIO/src/opentimelineio/anyDictionary.h:6,
from ./OpenTimelineIO/src/opentimelineio/serializableObject.h:9,
from ./OpenTimelineIO/src/opentimelineio/serializableObjectWithMetadata.h:6,
from ./OpenTimelineIO/src/opentimelineio/composable.h:6,
from ./OpenTimelineIO/src/opentimelineio/composable.cpp:4:
./OpenTimelineIO/src/opentimelineio/any.h:6:10: fatal error: any/any.hpp: No such file or directory
6 | #include "any/any.hpp"
| ^~~~~~~~~~~~~
compilation terminated.
make[2]: *** [src/opentimelineio/CMakeFiles/opentimelineio.dir/build.make:76: src/opentimelineio/CMakeFiles/opentimelineio.dir/clip.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
In file included from ./OpenTimelineIO/src/opentimelineio/anyDictionary.h:6,
from ./OpenTimelineIO/src/opentimelineio/serializableObject.h:9,
from ./OpenTimelineIO/src/opentimelineio/deserialization.cpp:7:
./OpenTimelineIO/src/opentimelineio/any.h:6:10: fatal error: any/any.hpp: No such file or directory
6 | #include "any/any.hpp"
| ^~~~~~~~~~~~~
compilation terminated.
make[2]: *** [src/opentimelineio/CMakeFiles/opentimelineio.dir/build.make:90: src/opentimelineio/CMakeFiles/opentimelineio.dir/composable.cpp.o] Error 1
make[2]: *** [src/opentimelineio/CMakeFiles/opentimelineio.dir/build.make:118: src/opentimelineio/CMakeFiles/opentimelineio.dir/deserialization.cpp.o] Error 1
In file included from ./OpenTimelineIO/src/opentimelineio/anyDictionary.h:6,
from ./OpenTimelineIO/src/opentimelineio/serializableObject.h:9,
from ./OpenTimelineIO/src/opentimelineio/serializableObjectWithMetadata.h:6,
from ./OpenTimelineIO/src/opentimelineio/effect.h:6,
from ./OpenTimelineIO/src/opentimelineio/effect.cpp:4:
./OpenTimelineIO/src/opentimelineio/any.h:6:10: fatal error: any/any.hpp: No such file or directory
6 | #include "any/any.hpp"
| ^~~~~~~~~~~~~
compilation terminated.
make[2]: *** [src/opentimelineio/CMakeFiles/opentimelineio.dir/build.make:132: src/opentimelineio/CMakeFiles/opentimelineio.dir/effect.cpp.o] Error 1
In file included from ./OpenTimelineIO/src/opentimelineio/anyDictionary.h:6,
from ./OpenTimelineIO/src/opentimelineio/serializableObject.h:9,
from ./OpenTimelineIO/src/opentimelineio/serializableObjectWithMetadata.h:6,
from ./OpenTimelineIO/src/opentimelineio/composable.h:6,
from ./OpenTimelineIO/src/opentimelineio/item.h:7,
from ./OpenTimelineIO/src/opentimelineio/composition.h:6,
from ./OpenTimelineIO/src/opentimelineio/composition.cpp:4:
./OpenTimelineIO/src/opentimelineio/any.h:6:10: fatal error: any/any.hpp: No such file or directory
6 | #include "any/any.hpp"
| ^~~~~~~~~~~~~
compilation terminated.
```

## To Reproduce

1. ArchLinux
2. Python 3.10 (sic)
4. git master
5. gcc 13.2.1

submodules initiated

まず ArchLinux のビルド失敗を再現し、any/any.hpp をインクルードする src/opentimelineio/any.h と、リポジトリの依存関係およびビルド設定を調査します。any.hpp 依存関係がどのように提供される想定なのかを確認し、その後、クリーンビルドが missing-header エラーなしで完了することを検証します。

索引モデルが issue の本文から書いたものです。