Add a minimal zwlr_foreign_toplevel activate test tool; confirm aegis's focus-staleness report no longer reproduces

tools/toplevel-activate: a standalone (not a workspace member - its own
empty [workspace] table, so building srdwm itself never has to build
this too) wayland-client + wayland-protocols-wlr binary that lists every
open zwlr_foreign_toplevel_handle_v1, activates one by index, and prints
the resulting `activated` state from the protocol's own feedback.
wayland-client 0.31.14 / wayland-protocols-wlr 0.3.12 - the exact
versions smithay 0.7.0 already pulls in, so this talks to the same real
client library srdwm itself is built against, not a possibly-drifted one.

Used it to reproduce aegis's own exact repro (nested `srdwm --wayland`,
two plain alacritty windows, activate the non-focused one, check
`srd clients`) precisely: launched a real nested instance, activated
back and forth 5 times, checked `srd clients` immediately and after a
delay each time. Every check matched the protocol's own `activated`
feedback - no staleness found, on the nested/winit backend specifically
(the peer's own repro environment). Documented in docs/TODO.md as
likely already fixed by other focus/window-management work since the
original report, not re-root-caused after the fact, but confirmed not
currently reproducible via the exact repro that found it - left open
one more round in case it resurfaces, with this tool as the fastest way
back to a live repro if it does.

1 files changed, 17 insertions, 0 deletions

diff --git a/tools/toplevel-activate/Cargo.toml b/tools/toplevel-activate/Cargo.toml
new file mode 100644
index 0000000..bbfe6fc
--- /dev/null
+++ b/tools/toplevel-activate/Cargo.toml
@@ -0,0 +1,17 @@
+[package]
+name = "toplevel-activate-test"
+version = "0.1.0"
+edition = "2021"
+
+# Standalone - deliberately not a member of the main workspace at
+# ../../Cargo.toml, so building/testing srdwm itself never has to build
+# this too. A debug tool, not part of the shipped product.
+[workspace]
+
+[[bin]]
+name = "activate"
+path = "src/main.rs"
+
+[dependencies]
+wayland-client = "=0.31.14"
+wayland-protocols-wlr = { version = "=0.3.12", features = ["client"] }