Add modular dev environment installer, dotfiles, and desnap script

Adds a TUI-driven, rollback-capable installer (install/install.sh +
install/modules/*.sh) covering JS/Python/systems toolchains, dev tooling,
browsers, chat apps, GNOME extras, and misc setup (wakatime key, ssh/gpg
perms, apt mirror benchmarking), all sourced from each vendor's official
install method. bootstrap.sh stows the zsh/git/tmux/vscode dotfiles and
runs the installer; desnap.sh purges snapd and replaces default snaps with
apt/Flatpak equivalents.

install/modules/telegram.sh

@@ -0,0 +1,23 @@
+install_telegram() {
+  if [[ -x /opt/Telegram/Telegram ]]; then ok "telegram already installed"; return; fi
+
+  local tarball
+  tarball=$(mktemp --suffix=.tar.xz)
+  curl -fsSL https://telegram.org/dl/desktop/linux -o "$tarball"
+  track_new_sudo_dir /opt/Telegram
+  sudo tar -xJf "$tarball" -C /opt
+  rm -f "$tarball"
+  sudo ln -sf /opt/Telegram/Telegram /usr/local/bin/telegram
+  rollback_push "sudo rm -f /usr/local/bin/telegram /usr/share/applications/telegram.desktop"
+
+  sudo tee /usr/share/applications/telegram.desktop >/dev/null <<'EOF'
+[Desktop Entry]
+Name=Telegram
+Exec=/opt/Telegram/Telegram -- %u
+Icon=/opt/Telegram/telegram.svg
+Terminal=false
+Type=Application
+Categories=Network;InstantMessaging;
+MimeType=x-scheme-handler/tg;
+EOF
+}