refactor code and add fallback prompt to zsh

profiles/base/.zsh/conf.d/01-vi-keybindings.zsh

@@ -0,0 +1,37 @@
+# Enable vi keybindings
+bindkey -v
+export KEYTIMEOUT=1
+autoload -z edit-command-line
+zle -N edit-command-line
+bindkey '^e' edit-command-line
+
+# Fix backspace character behavior in vi mode
+bindkey '^?' backward-delete-char
+bindkey '^W' backward-kill-word
+bindkey '^H' backward-delete-char # Control-h also deletes the previous char.
+bindkey '^U' backward-kill-line
+
+# Change cursor shape for different vi modes
+zle-keymap-select() {
+    if [[ ${KEYMAP} == vicmd ]] ||
+        [[ $1 == block ]]; then
+        echo -ne '\e[4 q'
+        psvar[1]="(cmd) "
+    elif [[ ${KEYMAP} == main ]] ||
+        [[ ${KEYMAP} == viins ]] ||
+        [[ -z ${KEYMAP} ]] ||
+        [[ $1 == beam ]]; then
+        echo -ne '\e[6 q'
+        psvar[1]="(ins) "
+    fi
+    zle reset-prompt
+}
+zle -N zle-keymap-select
+zle-line-init() {
+    zle -K viins # Initiate `vi insert` as keymap (can be removed if `bindkey -V` has been set elsewhere)
+    echo -ne '\e[6 q'
+    psvar[1]="(ins) "
+}
+zle -N zle-line-init
+echo -ne '\e[6 q' # Use beam shape cursor on startup
+preexec() { echo -ne '\e[6 q' } # Use beam shape cursor for each new prompt