feat: add nix shell

[rawkode]

No description provided.

[codecov-commenter]

Codecov Report

Merging #158 (e458d1e) into main (f8ca7f1) will increase coverage by 3.58%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #158      +/-   ##
==========================================
+ Coverage   48.06%   51.65%   +3.58%     
==========================================
  Files          51       51              
  Lines        1966     1845     -121     
==========================================
+ Hits          945      953       +8     
+ Misses       1021      892     -129     

Impacted Files	Coverage Δ
src/actions/directory/mod.rs	0.00% <0.00%> (ø)
src/actions/package/providers/yay.rs	0.00% <0.00%> (ø)
src/actions/package/providers/pkgin.rs	0.00% <0.00%> (ø)
src/actions/package/providers/bsdpkg.rs	0.00% <0.00%> (ø)
src/actions/package/providers/winget.rs	0.00% <0.00%> (ø)
src/actions/package/providers/homebrew.rs	0.00% <0.00%> (ø)
src/contexts/os.rs	96.42% <0.00%> (+0.13%)	⬆️
src/actions/file/copy.rs	14.06% <0.00%> (+0.42%)	⬆️
src/contexts/mod.rs	84.05% <0.00%> (+0.47%)	⬆️
src/actions/file/link.rs	92.92% <0.00%> (+0.92%)	⬆️
... and 22 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update f8ca7f1...e458d1e. Read the comment docs.

[icepuma]

I cannot say anything about the nix shell. Can you ask someone who is more capable of doing the review?

[rawkode]

As this doesn't affect Comtrya itself and only provides some build support; I'll merge as is.