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.

zsh/.zsh_aliases

@@ -0,0 +1,9 @@
+alias ls='eza'
+alias ll='eza -lah'
+alias la='eza -a'
+alias lt='eza --tree'
+alias grep='rg'
+alias gs='git status'
+alias gd='git diff'
+alias gco='git checkout'
+alias dc='docker compose'

zsh/.zshrc

@@ -0,0 +1,15 @@
+HISTFILE="$HOME/.zsh_history"
+HISTSIZE=50000
+SAVEHIST=50000
+setopt HIST_IGNORE_DUPS SHARE_HISTORY EXTENDED_HISTORY INC_APPEND_HISTORY
+
+autoload -Uz compinit && compinit
+
+export EDITOR="vim"
+export PATH="$HOME/.local/bin:$PATH"
+
+[[ -f "$HOME/.zsh_aliases" ]] && source "$HOME/.zsh_aliases"
+
+PROMPT='%F{blue}%~%f %(?.%F{green}.%F{red})❯%f '
+
+# --- devenv installers (managed by install/lib.sh profile_add, appended below) ---