This is a direct followup to #13557 which caches additional attributes that were added in #24095 that are expensive to compute. I had to reopen#25556 in another PR to invalidate the GitLab CI cache, but see #25556 for prior discussion.
### Before
```console
$ time spack env activate .
real 2m13.037s
user 1m25.584s
sys 0m43.654s
$ time spack env view regenerate
==> Updating view at /Users/Adam/.spack/.spack-env/view
real 16m3.541s
user 10m28.892s
sys 4m57.816s
$ time spack env deactivate
real 2m30.974s
user 1m38.090s
sys 0m49.781s
```
### After
```console
$ time spack env activate .
real 0m8.937s
user 0m7.323s
sys 0m1.074s
$ time spack env view regenerate
==> Updating view at /Users/Adam/.spack/.spack-env/view
real 2m22.024s
user 1m44.739s
sys 0m30.717s
$ time spack env deactivate
real 0m10.398s
user 0m8.414s
sys 0m1.630s
```
Fixes#25555Fixes#25541
* Speedup environment activation, part 2
* Only query distutils a single time
* Fix KeyError bug
* Make vermin happy
* Manual memoize
* Add comment on cross-compiling
* Use platform-specific include directory
* Fix multiple bugs
* Fix python_inc discrepancy
* Fix import tests