refactor: move helper scripts into .bin folder and update tasks.json

.bin/nvim-workspace.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+
+XDG_CONFIG_HOME="$PWD/.config" \
+  XDG_DATA_HOME="$PWD/.local/share" \
+  XDG_STATE_HOME="$PWD/.state" \
+  XDG_CACHE_HOME="$PWD/.cache" \
+  TMUX="" \
+  tmux new-session -s dev -n editor 'nvim'