logiguard fork v2: patched GPUI on verified 8c74db0 tree

Rebuilt from the exact zed-industries/zed @ 8c74db00c4053d6c0a9037863d7bd048658da4ca
tree (previous orphan was based on a stale/wrong fetch). Same 3-file patch:
  - serial.rs: add SerialKind::KeyboardEnter
  - client.rs: store wl_keyboard.enter serial; add latest_serial_of()
  - window.rs: activate() uses keyboard-enter serial (Mutter focus gate)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

nix/dev/flake.nix

@@ -0,0 +1,10 @@
+{
+  description = "Private inputs for development purposes. These are used by the top level flake in the `dev` partition, but do not appear in consumers' lock files.";
+
+  inputs = {
+    treefmt-nix.url = "github:numtide/treefmt-nix";
+  };
+
+  # This flake is only used for its inputs.
+  outputs = { ... }: { };
+}