Add bos-update + replicate the dev zsh shell

bos-update: one command that updates both BOS channels — pacman -Syu (snap-pac
snapshotted) and bakery update --all — best-effort so one failing doesn't abort
the other. Baked into the live env and skel.

Shell: match the dev laptop's zsh. Ship Powerlevel10k + zsh-autosuggestions,
zsh-history-substring-search and zsh-syntax-highlighting, sourced from the distro
packages (no oh-my-zsh framework) in the correct order, plus the dev .p10k.zsh.
Powerlevel10k is AUR-only, so it's republished to [breadway] via
packaging/powerlevel10k + a CI workflow (builds libgit2 + gitstatus from source),
same pattern as bibata / zen-browser-bin. skel/.zshrc keeps the BOS QoL aliases
and pywal palette import, with `update` aliased to bos-update.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packaging/powerlevel10k/PKGBUILD

@@ -0,0 +1,105 @@
+# BOS in-house rebuild of zsh-theme-powerlevel10k (AUR-only upstream).
+# Republished to [breadway] so the ISO can pull the BOS default prompt via pacman
+# (same pattern as bibata / zen-browser-bin). Upstream maintainer header kept below.
+# Maintainer: Mark Wagie <mark dot wagie at proton dot me>
+# Contributor: Christian Rebischke <chris.rebischke@archlinux.org>
+# Contributor: Jeff Henson <jeff@henson.io>
+# Contributor: Ron Asimi <ron dot asimi at gmail dot com>
+# Contributor: Roman Perepelitsa <roman.perepelitsa@gmail.com>
+pkgname=zsh-theme-powerlevel10k
+# Whenever pkgver is updated, _libgit2ver below must also be updated.
+pkgver=1.20.17  ## see P9K_VERSION in internal/p10k.zsh
+_libgit2ver="tag-2ecf33948a4df9ef45a66c68b8ef24a5e60eaac6"
+pkgrel=1
+epoch=1
+pkgdesc="Powerlevel10k is a theme for Zsh. It emphasizes speed, flexibility and out-of-the-box experience."
+arch=('x86_64' 'aarch64')
+url='https://github.com/romkatv/powerlevel10k'
+license=('MIT')
+depends=(
+  'glibc'
+  'zsh'
+)
+makedepends=(
+  'git'
+  'cmake'
+)
+optdepends=(
+  # It works well with Nerd Fonts, Source Code Pro, Font Awesome, Powerline,
+  # and even the default system fonts. The full choice of style options is
+  # available only when using Nerd Fonts.
+  'ttf-meslo-nerd-font-powerlevel10k: recommended font'
+  'powerline-fonts: patched fonts for powerline'
+  'ttf-font-nerd: full choice of style options'
+)
+replaces=('zsh-theme-powerlevel9k')
+_commit=9253fb1c5034410c43a0c681ff8294181c54016c
+
+# _libgit2ver depends on pkgver. They must be updated together. See libgit2_version in:
+# https://raw.githubusercontent.com/romkatv/powerlevel10k/v${pkgver}/gitstatus/build.info
+source=(
+  "git+https://github.com/romkatv/powerlevel10k.git#commit=${_commit}"
+#  "powerlevel10k-${pkgver}.tar.gz::https://github.com/romkatv/powerlevel10k/archive/v${pkgver}.tar.gz"
+#  "https://github.com/romkatv/powerlevel10k/releases/download/v$pkgver/powerlevel10k-$pkgver.tar.gz.asc"
+  "libgit2-${_libgit2ver}.tar.gz::https://github.com/romkatv/libgit2/archive/${_libgit2ver}.tar.gz")
+sha256sums=('f0edc2cc5bfcdfcf3b94f10597c252873567a990e651d04059c887046fba6701'
+            '4ce11d71ee576dbbc410b9fa33a9642809cc1fa687b315f7c23eeb825b251e93')
+#validpgpkeys=('8B060F8B9EB395614A669F2A90ACE942EB90C3DD') # Roman Perepelitsa <roman.perepelitsa@gmail.com>
+
+build() {
+  cd "libgit2-${_libgit2ver}"
+  local cmake_options=(
+    -W no-dev
+    -D CMAKE_BUILD_TYPE='None'
+    -D ZERO_NSEC='ON'
+    -D THREADSAFE='ON'
+    -D USE_BUNDLED_ZLIB='ON'
+    -D REGEX_BACKEND='builtin'
+    -D USE_HTTP_PARSER='builtin'
+    -D USE_SSH='OFF'
+    -D USE_HTTPS='OFF'
+    -D BUILD_CLAR='OFF'
+    -D USE_GSSAPI='OFF'
+    -D USE_NTLMCLIENT='OFF'
+    -D BUILD_SHARED_LIBS='OFF'
+    -D ENABLE_REPRODUCIBLE_BUILDS='ON'
+  )
+  cmake "${cmake_options[@]}" .
+  make
+
+  # build gitstatus
+  cd "$srcdir/powerlevel10k/gitstatus"
+  export CXXFLAGS+=" -I${srcdir}/libgit2-${_libgit2ver}/include -DGITSTATUS_ZERO_NSEC -D_GNU_SOURCE"
+  export LDFLAGS+=" -L${srcdir}/libgit2-${_libgit2ver}"
+  make
+}
+
+package() {
+  cd powerlevel10k
+  find . -type f -exec install -D '{}' "$pkgdir/usr/share/${pkgname}/{}" ';'
+
+  install -d "${pkgdir}/usr/share/licenses/${pkgname}"
+  ln -s "/usr/share/${pkgname}/LICENSE" "${pkgdir}/usr/share/licenses/${pkgname}"
+
+  # delete unnecessary files. See also: https://bugs.archlinux.org/task/66737
+  rm -r "${pkgdir}/usr/share/${pkgname}/.git"
+  rm -r "${pkgdir}/usr/share/${pkgname}/gitstatus/deps/"
+  rm -r "${pkgdir}/usr/share/${pkgname}/gitstatus/obj"
+  rm -r "${pkgdir}/usr/share/${pkgname}/gitstatus/src/"
+  rm -r "${pkgdir}/usr/share/${pkgname}/gitstatus/.vscode/"
+  rm "${pkgdir}/usr/share/${pkgname}/.gitattributes"
+  rm "${pkgdir}/usr/share/${pkgname}/.gitignore"
+  rm "${pkgdir}/usr/share/${pkgname}/Makefile"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/build"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/Makefile"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/mbuild"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/.clang-format"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/.gitignore"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/.gitattributes"
+  rm "${pkgdir}/usr/share/${pkgname}/gitstatus/usrbin/.gitkeep"
+
+  cd "${pkgdir}/usr/share/${pkgname}"
+  for file in *.zsh-theme internal/*.zsh gitstatus/*.zsh gitstatus/install; do
+    zsh -fc "emulate zsh -o no_aliases && zcompile -R -- $file.zwc $file"
+  done
+}