Share a chosen workspace folder and stop with the window

run.sh asks which host folder Claude may access, using the desktop's
folder picker (zenity, or kdialog on KDE; terminal prompt otherwise),
and mounts it read-write at /workspace. It opens at the last folder
used, refuses / and $HOME, and can be skipped with --workspace DIR.
The image creates /workspace and a ~/workspace symlink to it.

Closing Claude Desktop's window only hides the app, which left the
container running invisibly. The new entrypoint launch-claude.sh
watches the app's X windows and quits it once none is open or
minimized, so the container exits with it. run.sh adds --init for
signal handling and reaping.

Also add .gitignore for workspace/ and .env.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

launch-claude.sh

@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+# Container entrypoint: run Claude Desktop and stop when its window is closed.
+#
+# Closing the window only hides the app (it keeps running for the tray icon,
+# which GNOME doesn't show), so the container would keep running invisibly.
+# This watches the app's X windows and quits the app once none of them is
+# open or minimized. The container then exits with it.
+
+set -u
+
+claude-desktop "$@" &
+app=$!
+
+stop_app() { kill -TERM "$app" 2>/dev/null; wait "$app"; exit $?; }
+trap stop_app TERM INT HUP
+
+host="$(hostname)"
+
+# True if any of this container's Claude windows is Normal (shown) or Iconic
+# (minimized). A closed window is Withdrawn or loses WM_STATE altogether.
+# WM_CLIENT_MACHINE filters out Claude windows from other containers or apps
+# on the same X server.
+window_open() {
+    local w props
+    for w in $(xwininfo -root -tree 2>/dev/null \
+               | awk '/\("com\.anthropic\.claude" "com\.anthropic\.Claude"\)/ {print $1}'); do
+        props="$(xprop -id "$w" WM_CLIENT_MACHINE WM_STATE 2>/dev/null)" || continue
+        [[ "$props" == *"WM_CLIENT_MACHINE(STRING) = \"$host\""* ]] || continue
+        [[ "$props" =~ "window state: "(Normal|Iconic) ]] && return 0
+    done
+    return 1
+}
+
+seen=0    # only arm the check after the first window has appeared
+misses=0  # require a few consecutive misses to ride out brief remaps
+while kill -0 "$app" 2>/dev/null; do
+    sleep 1 & wait $!
+    if window_open; then
+        seen=1 misses=0
+    elif (( seen )) && (( ++misses >= 3 )); then
+        echo "launch-claude: window closed, quitting Claude Desktop" >&2
+        stop_app
+    fi
+done
+
+wait "$app"