valent: use overlay to fix build

flake.nix

@@ -35,6 +35,7 @@
           overlays = [
             nix-vscode-extensions.overlays.default
             niri.overlays.niri
+            (import ./overlays/valent.nix)
           ];
           config = {
             allowUnfree = true;

overlays/valent.nix

@@ -0,0 +1,26 @@
+final: prev: {
+  valent = prev.valent.overrideAttrs (old: {
+    nativeBuildInputs =
+      old.nativeBuildInputs
+      ++ (with prev.pkgs; [
+        vala
+      ]);
+    buildInputs =
+      old.buildInputs
+      ++ (with prev.pkgs; [
+        libportal
+        libportal-gtk4
+        tracker
+        gdk-pixbuf
+        libphonenumber
+      ]);
+    version = "v1.0.0.alpha.46";
+    src = prev.fetchFromGitHub {
+      owner = "andyholmes";
+      repo = "valent";
+      rev = "165a2791d4bf3e7dee69e3dd7885dbe4948265b9";
+      hash = "sha256-7klvOvwyAg+Xno6zWo8UByjaS9OkOuCceuZcAIEgdyU=";
+      fetchSubmodules = true;
+    };
+  });
+}