Sync codex-desktop-linux with v0.2.9 release content

[github-actions]

v0.2.9 released. Update codex-desktop-linux to pin/ship this version and mirror the relevant changes.

v0.2.9 changelog

Fixed

• GTK4 applications (Nautilus, Text Editor, baobab, and others) now return their
  full accessibility tree instead of a single role: "unknown" root with
  child_count: 0. Reads were routed through the atspi P2P trait's
  object_as_accessible, whose no-peer fallback builds a proxy with a path but
  no destination; on the shared a11y bus that fails with ServiceUnknown for
  any app that does not advertise a peer-to-peer bus address. Modern GTK4 apps
  do not implement the legacy GetApplicationBusAddress, so they hit the broken
  fallback while GTK3/Chromium/Electron apps kept working. Reads now use
  ObjectRefExt::as_accessible_proxy, which always pins the destination to the
  object's bus name. (GTK4 apps return empty accessibility tree (1 "unknown" node) — likely atspi crate GTK4 object-path handling #31)

---

Opened automatically by the release workflow.

[avifenesh]

Downstream sync PR opened against ilysenko/codex-desktop-linux: https://github.com/ilysenko/codex-desktop-linux/pull/543\n\nThe v0.2.9 GTK4 AT-SPI fix was ported and live-checked with Nautilus: the embedded binary returned a real org.gnome.Nautilus application/window tree rather than the prior empty unknown-root shape.