feat(zsh): make <C-l> retain initial new line of pure prompt

.config/zsh/config/prompt.zsh

@@ -18,3 +18,18 @@ prompt pure
 # Prompt styles.
 zstyle :prompt:pure:prompt:error color 1
 zstyle :prompt:pure:prompt:success color 15
+
+# This clear screen widget allows Pure to re-render with its initial
+# newline by manually clearing the screen and placing the cursor on
+# line 4 so that the prompt is redisplayed on lines 2 and 3.
+custom_prompt_pure_clear_screen() {
+  # Enable output to terminal.
+  zle -I
+
+  # Clear screen and move cursor to (4, 0).
+  print -n '\e[2J\e[4;0H'
+
+  # Redraw prompt.
+  zle .redisplay
+}
+zle -N clear-screen custom_prompt_pure_clear_screen