chore(lib/treewide): cleanup directory struture of lib. See lib/readme.md for details

lib/introspection/flake-module.nix

@@ -0,0 +1,40 @@
+{ self, inputs, ... }:
+let
+  inputOverrides = builtins.concatStringsSep " " (
+    builtins.map (input: " --override-input ${input} ${inputs.${input}}") (builtins.attrNames inputs)
+  );
+in
+{
+  perSystem =
+    {
+      pkgs,
+      system,
+      lib,
+      ...
+    }:
+    let
+      tests = import ./test.nix { inherit lib; };
+    in
+    {
+      legacyPackages.evalTests-values = tests;
+      checks = {
+        lib-values-eval = pkgs.runCommand "tests" { nativeBuildInputs = [ pkgs.nix-unit ]; } ''
+          export HOME="$(realpath .)"
+
+          nix-unit --eval-store "$HOME" \
+            --extra-experimental-features flakes \
+            ${inputOverrides} \
+            --flake ${
+              self.filter {
+                include = [
+                  "flakeModules"
+                  "lib"
+                ];
+              }
+            }#legacyPackages.${system}.evalTests-values
+
+          touch $out
+        '';
+      };
+    };
+}