Bug#1110745: console-setup: keyboard is broken after upgrade from bookworm to trixie

[Trần H. Trung <work@trung.fun>]

Package: console-setup
Version: 1.240
Severity: critical
Justification: breaks the whole system
X-Debbugs-Cc: work@trung.fun

Keyboard map was overwritten when upgrade from bookworm to trixie.

I was unable to log-in since I can not use my own keyboard symbols map.
My password was interpreted with wrong symbols since they were modified
by the upgrade.

The apt/installer/upgrader should have checked by `diff` and prompt user
when found changes in the current mapping which in my case was
configured by this line:

```
* keyboard-configuration/layoutcode: vn,us
```

This bug would affect anyone who customizes their own keyboard with X11
and potentially be locked-out of their own system forever.

-- System Information:
Debian Release: 13.0
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.12.38+deb13-amd64 (SMP w/32 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE=en_GB:en
Shell: /bin/sh linked to /usr/bin/dash
Init: OpenRC (via /run/openrc), PID 1: init
LSM: AppArmor: enabled

Versions of packages console-setup depends on:
ii  console-setup-linux     1.240
ii  debconf [debconf-2.0]   1.5.91
ii  keyboard-configuration  1.240
ii  xkb-data                2.42-1

console-setup recommends no packages.

Versions of packages console-setup suggests:
ii  locales                    2.41-12
ii  sysvinit-utils [lsb-base]  3.14-4

Versions of packages keyboard-configuration depends on:
ii  debconf [debconf-2.0]   1.5.91
ii  liblocale-gettext-perl  1.07-7+b1
ii  xkb-data                2.42-1

Versions of packages console-setup-linux depends on:
ii  init-system-helpers     1.68
ii  initscripts             3.14-4
ii  kbd                     2.7.1-2
ii  keyboard-configuration  1.240

console-setup-linux suggests no packages.

Versions of packages console-setup is related to:
pn  console-common        <none>
pn  console-data          <none>
pn  console-tools         <none>
pn  gnome-control-center  <none>
ii  kbd                   2.7.1-2
ii  systemd               257.7-1

-- debconf information:
* keyboard-configuration/xkb-keymap: us
* console-setup/fontsize-fb47: 8x16
* keyboard-configuration/altgr: The default for the keyboard layout
* keyboard-configuration/variant: English (US)
* console-setup/fontface47: Fixed
  keyboard-configuration/unsupported_config_layout: true
  console-setup/codesetcode: Vietnamese
  console-setup/fontsize-text47: 8x16
  console-setup/fontsize: 8x16
  keyboard-configuration/unsupported_config_options: true
  console-setup/use_system_font:
* keyboard-configuration/store_defaults_in_debconf_db: true
  console-setup/store_defaults_in_debconf_db: true
* keyboard-configuration/model: Generic 104-key PC
  keyboard-configuration/unsupported_options: true
* keyboard-configuration/layout:
  console-setup/framebuffer_only:
  keyboard-configuration/unsupported_layout: true
* keyboard-configuration/layoutcode: vn,us
* console-setup/codeset47: . Latin - Vietnamese
* keyboard-configuration/other:
* keyboard-configuration/compose: No compose key
  console-setup/guess_font:
* keyboard-configuration/toggle: No toggling
* keyboard-configuration/switch: No temporary switch
  debian-installer/console-setup-udeb/title:
* keyboard-configuration/optionscode: caps:swapescape,compose:sclk
* keyboard-configuration/variantcode:
* console-setup/charmap47: UTF-8
  keyboard-configuration/ctrl_alt_bksp: false
* keyboard-configuration/modelcode: pc104