Fix: Bootstrap oh-my-zsh, its plugins and the bar's Cascadia font on new installs

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

bootstrap.sh

@@ -124,6 +124,24 @@ for app in $(packages installer); do
     esac
 done
 
+step "oh-my-zsh and plugins"
+# .zshrc sources ~/.oh-my-zsh/oh-my-zsh.sh and loads two custom plugins from it.
+# A plain clone is all oh-my-zsh needs; its installer would also write a template
+# ~/.zshrc, which then conflicts with the stowed one.
+if [[ ! -d "$HOME/.oh-my-zsh" ]]; then
+    git clone --depth 1 https://github.com/ohmyzsh/ohmyzsh.git "$HOME/.oh-my-zsh"
+else
+    echo "oh-my-zsh: already installed"
+fi
+zsh_custom="$HOME/.oh-my-zsh/custom/plugins"
+for plugin in zsh-autosuggestions zsh-syntax-highlighting; do
+    if [[ -d "$zsh_custom/$plugin" ]]; then
+        echo "$plugin: already installed"
+    else
+        git clone --depth 1 "https://github.com/zsh-users/$plugin" "$zsh_custom/$plugin"
+    fi
+done
+
 # --- Optional: SVT-AV1 essential + ffmpeg rebuild ----------------------------
 
 if [[ $svt_av1 == ask ]]; then