Bump setuptools and setuptools_scm requirements to solve uv2nix issue

[akaihola]

Update the build-system requirements in pyproject.toml to setuptools >= 80 and setuptools_scm > 8.

This solves the missing [toml] extra issue when using uv2nix:

error:
… while calling the 'derivationStrict' builtin
 at <nix/derivation-internal.nix>:37:12:
   36|
   37|   strict = derivationStrict drvAttrs;
     |            ^
   38|

… while evaluating derivation 'nix-shell'
 whose name attribute is located at /nix/store/as8ksm9hafq3x3cvml95i5s092903kvk-source/pkgs/stdenv/generic/make-derivation.nix:541:13

… while evaluating attribute 'nativeBuildInputs' of derivation 'nix-shell'
 at /nix/store/as8ksm9hafq3x3cvml95i5s092903kvk-source/pkgs/stdenv/generic/make-derivation.nix:590:13:
  589|             depsBuildBuild = elemAt (elemAt dependencies 0) 0;
  590|             nativeBuildInputs = elemAt (elemAt dependencies 0) 1;
     |             ^
  591|             depsBuildTarget = elemAt (elemAt dependencies 0) 2;

(stack trace truncated; use '--show-trace' to show the full, detailed trace)

error: Extra/group name 'toml' does not match either extra or dependency group

For some reason pip and uv alone aren't bothered by

requires = ["setuptools>=61.0", "setuptools_scm[toml]>=6.2", "wheel"]

even though recent versions of setuptools_scm do not have the [toml] extra for optional dependencies. But uv2nix seems to be more sensitive.