eos fails to build if $MESA_CACHES_DIR is set and contains data from a sufficiently different MESA version

Nobody has claimed this yet.

**Describe the issue**
The `eos` module fails to build if `$MESA_CACHES_DIR` is set and contains data from a sufficiently different MESA version. In this case `$MESA_CACHES_DIR` had data from 11701. The same happens the other way around, if `$MESA_CACHES_DIR` pointed to r24.08.1 data when installing 11701.

As a side note, is there anything preventing me from shooting myself in the foot when running models whilst pointing to a cache directory with incompatible data?

**System information**
- MESA version: r24.08.1, 11701
- MESA SDK version: x86_64-linux-24.7.1, x86_64-linux-20190503
- Operating system: Debian GNU/Linux 12 (bookworm)

**Output from `./help`**
```
MESA Version
r24.08.1

uname -a
Linux bndfa-d068168w 6.8.0-49-generic #49~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Wed Nov 6 17:42:15 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

gfortran -v
Using built-in specs.
COLLECT_GCC=/home/walter/Software/MESA/sdk/mesasdk24.7.1/bin/gfortran.exec
COLLECT_LTO_WRAPPER=/home/walter/Software/MESA/sdk/mesasdk24.7.1/bin/../libexec/gcc/x86_64-pc-linux-gnu/13.3.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /home/user/sdk2-tmp/build/gcc/configure CC= CXX= --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=x86_64-pc-linux-gnu --prefix=/home/user/sdk2-tmp/mesasdk --with-gmp=/home/user/sdk2-tmp/mesasdk --with-mpfr=/home/user/sdk2-tmp/mesasdk --with-mpc=/home/user/sdk2-tmp/mesasdk --enable-languages=c,c++,fortran --disable-multilib --disable-nls --enable-clocale=generic
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.3.0 (GCC)

$MESASDK_ROOT
/home/walter/Software/MESA/sdk/mesasdk24.7.1

MESASDK version
x86_64-linux-24.7.1

$PATH
/home/walter/Software/MESA/sdk/mesasdk24.7.1/bin:/home/walter/.venv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin

$MESA_DIR
/home/walter/Software/MESA/mesa-24.08.1

```

**Build log**
[build.log](https://github.com/user-attachments/files/19007589/build.log)

Start by reviewing the attached build.log and the eos module build path, then reproduce the failure with MESA versions r24.08.1 and 11701 sharing incompatible $MESA_CACHES_DIR data. Done means the build handles incompatible cache contents safely or reports a clear diagnostic, with model use of mismatched cache data addressed if covered by the investigation.

Written by the indexing model from the issue text.