* [update] bump version; add link to discourse.group (#930)

* [refactor] get rid of template in radial_integrals_sum_L3() (#932)

* apply @simonpintarelli proposed code change

* get rid of one more tempale

* default: -> throw, whitespace

* fix

* apply format

---------

Co-authored-by: Simon Pintarelli <simon.pintarelli@cscs.ch>

* [fix] subspace initialization in test_lr_solver (#934)

* [cmake] remove std::filesystem target (#936)

std::filesystem is part of C++17 which is required via CXX_STANDARD, there is no
need to check for it explicitly

* [fix] compilation error for ~memory_pool+tests (#939)

* Ci/rebuild base image (#942)

* CI: rebuild base images / pin spack to v0.21
* CI: use anonymous environments instead of dev-build with SPEC
* avoid creating partitions with empty intervals in COSTA `custom_layout`



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Co-authored-by: Anton Kozhevnikov <toxa81@gmail.com>

* [fix] truncate very small occupation numbers to 0 (#943)

* [refactor] minor cleaups (#938)

* minor cleaups
* apply format

* [cmake] add missing REQUIRED (#945)

* [fix] scalar-relativistic radial solver (#941)

Introduce a few fixes for the scalar-relativistic radial solver.

* [feature] port lr_addusdens to sirius (#937)

Use a different sequence of operations to compute G+q augmentation charge.

---------

Co-authored-by: Simon Pintarelli <simon.pintarelli@cscs.ch>
Co-authored-by: Simon Pintarelli <1237199+simonpintarelli@users.noreply.github.com>