Add in-guest acceptance test suite

Runs inside a live Omarchy session (typically a VM installed by
omarchy-iso-test) and verifies the desktop actually works: session
health, application launches by window class, and shell surfaces via
IPC — including typing into the launcher and launching the top hit.

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

test/acceptance.d/apps-test.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+set -euo pipefail
+
+source "$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)/base-test.sh"
+
+launch_and_verify() {
+  local name="$1" command="$2" class="$3"
+
+  # A pre-existing window makes the test ambiguous (and closing it would be
+  # hostile on a dev machine) — acceptance runs expect a fresh session.
+  if window_present "$class" >/dev/null 2>&1; then
+    fail "$name starts with no pre-existing window" "a window matching $class is already open"
+  fi
+
+  launch_app "$command"
+  wait_until "$name opens a window" 90 window_present "$class"
+  sleep 1
+  screenshot "app-$name"
+
+  local deadline=$((SECONDS + 30))
+  while window_present "$class" >/dev/null 2>&1; do
+    close_windows "$class"
+
+    if ((SECONDS >= deadline)); then
+      fail "$name window closes"
+    fi
+
+    sleep 2
+  done
+  pass "$name window closes"
+}
+
+# name|command|window class regex
+apps='terminal|foot|^foot$
+browser|chromium --new-window|(?i)chromium
+files|nautilus --new-window|org.gnome.Nautilus
+calculator|gnome-calculator|org.gnome.Calculator
+notes|obsidian|(?i)obsidian
+office|libreoffice|(?i)(soffice|libreoffice)
+pdf-viewer|evince|(?i)evince'
+
+while IFS='|' read -r name command class; do
+  launch_and_verify "$name" "$command" "$class"
+done <<<"$apps"