feat: settle Chrome's window, crash bubble and password prompts

Three things a volunteer should never have to see.

Sway was drawing its own title bar above Chrome's tab strip, which
already carries the window controls. Verified on a real session: Chrome
is an xdg_shell client with app_id "google-chrome" and sway was giving
it border "normal". A scoped rule removes the compositor decoration
only — Chrome keeps its tabs and address bar, stays a normal window, and
still maximises and minimises. A class rule covers an XWayland fallback.
Nothing else changes: the only other window in this classroom is VLC,
which is already borderless, so no broader rule is warranted.

"Restore pages? Chrome didn't shut down correctly" is suppressed with
--hide-crash-restore-bubble. Note the name. The switch this was going to
use, --disable-session-crashed-bubble, is not present in Chrome 152 at
all — checked against the strings of the installed binary — so it would
have silently done nothing.

That hides the prompt; the profile was still being marked as crashed,
which is the untidy half. Chrome's browser process shuts down cleanly on
SIGTERM, so a shutdown unit now gives it one and waits up to eight
seconds before the session is torn out from under it. Best effort by
construction: a shutdown that will not finish is far worse than a crash
flag.

Password prompts go off with the PasswordManagerEnabled policy, on the
path the classroom already manages. Existing profile and session data
are untouched, and website logins are unaffected: Wonder Ink and YouTube
stay signed in.

Co-Authored-By: Claude Opus 5 <[email protected]>

config/sway/config

@@ -24,6 +24,18 @@ exec --no-startup-id /usr/local/bin/classroom-dock
 
 include /etc/sway/config.d/*
 
+# Chrome draws its own tab strip with window controls in it, so sway's
+# title bar above that is a second, redundant one. Verified on the
+# endpoint: Chrome is an xdg_shell client with app_id "google-chrome",
+# and sway was giving it border "normal". The class rule covers the case
+# where Chrome falls back to XWayland.
+#
+# This removes the compositor's decoration only. Chrome keeps its tabs
+# and address bar, stays a normal window, and still maximises and
+# minimises exactly as before.
+for_window [app_id="google-chrome"] border none
+for_window [class="(?i)google-chrome"] border none
+
 # The DVD player is an appliance screen, not a desktop window. VLC takes
 # the whole display itself; this removes the title bar sway would
 # otherwise draw above the video. classroom-dvd-session covers the