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>

crates/vim/README.md

@@ -0,0 +1,36 @@
+This contains the code for Zed's Vim emulation mode.
+
+Vim mode in Zed is supposed to primarily "do what you expect": it mostly tries to copy vim exactly, but will use Zed-specific functionality when available to make things smoother. This means Zed will never be 100% vim compatible, but should be 100% vim familiar!
+
+The backlog is maintained in the `#vim` channel notes.
+
+## Testing against Neovim
+
+If you are making a change to make Zed's behavior more closely match vim/nvim, you can create a test using the `NeovimBackedTestContext`.
+
+For example, the following test checks that Zed and Neovim have the same behavior when running `*` in visual mode:
+
+```rust
+#[gpui::test]
+async fn test_visual_star_hash(cx: &mut gpui::TestAppContext) {
+    let mut cx = NeovimBackedTestContext::new(cx).await;
+
+    cx.set_shared_state("ˇa.c. abcd a.c. abcd").await;
+    cx.simulate_shared_keystrokes(["v", "3", "l", "*"]).await;
+    cx.assert_shared_state("a.c. abcd ˇa.c. abcd").await;
+}
+```
+
+To keep CI runs fast, by default the neovim tests use a cached JSON file that records what neovim did (see crates/vim/test_data),
+but while developing this test you'll need to run it with the neovim flag enabled:
+
+```sh
+cargo test -p vim --features neovim test_visual_star_hash
+```
+
+This will run your keystrokes against a headless neovim and cache the results in the test_data directory. Note that neovim must be installed and reachable on your $PATH in order to run the feature.
+
+
+## Testing zed-only behavior
+
+Zed does more than vim/neovim in their default modes. The `VimTestContext` can be used instead. This lets you test integration with the language server and other parts of zed's UI that don't have a NeoVim equivalent.