Tracy: autotools setup

Well, this was as painful as expected.

Introducing a proper autotool-based tracy build. I don't think this is
the right approach, but hey, it works.

Tracy is not distributing any pkg-config file, so we had to fallback
to a more "manual" method to propagate the headers path. Instead of
having a plain enable/disable flag, we send the path to the tracy
/public subfolder (~= $out in the Tracy Nix derivation).

The flake Nixpkgs is currently pointing to 23.05. The tracy derivation
was only building the visualizer, not the client library back then. We
introduce a 23.11 Nixpkgs and build its Tracy derivation with the
23.05 toolchain to go around some glibc ABI incompatibilities.

Kudos to Mic92 for the help for the flake bit.

Co-authored-by: Jörg Thalheim <joerg@thalheim.io>

flake.nix

@@ -196,7 +196,12 @@
               # To go around that issue, we build the 23.11 tracy
               # derivation with the 23.05 toolchain/libs.
               tracy = final.callPackage (nixpkgs-tracy.legacyPackages.${final.hostPlatform.system}.path + "/pkgs/development/tools/tracy") {};
+              # Temporarily enabling the tracy profiler and disabling
+              # install check for convenience.
+              # TODO: remove this before undrafting the PR.
               enableTracy = true;
+              doCheck = false;
+              doInstallCheck = false;
               officialRelease = false;
               boehmgc = final.boehmgc-nix;
               libgit2 = final.libgit2-nix;