buildNimSbom: support the nimRelease attr

Add FOD data during "nim_lk add --component:…"

tests: fix purl test

Tup: add nim_lk program to ../<nim_lk> group

Implement "nim_lk add --component:…"

Rename purl module to purls

Rename pkg/ to src/

*.nimble: swap nim:bin key and value

build-nim-sbom.nix: fix for nixos-24.05

bom-to-nim-cfg.nix: add extraPaths parameter

Add extraConfig to bom-to-nim-cfg.nix

bom-to-nim-cfg.nix: remove the pkg directory

Add Nix note to README

build-nim-sbom: implement that overrideSbom function

Use JQ to generate Tup build rules

Update nimble dependency

Update "source-distribution" URLs during component update

Use fork of Nimble

build-nim-sbom.nix: swap order of arguments

Simplify build-nim-sbom.nix

Only pass finalAttrs to callers, do not pass prevAttrs.
This drastically simplifies things.