feat(run): allow run files in notes directories

Move `run` from a simple alias to a function which checks a for a
`.notes/run` file first or defaults back to the previous functionality
and uses a file in the current directory.

roles/zsh/files/config/functions/run

@@ -0,0 +1,8 @@
+# Execute a "run" file either within ".notes" or the current directory.
+function run {
+  if [[ -f .notes/run ]]; then
+    .notes/run "${@}"
+  elif [[ -f run ]]; then
+    ./run "${@}"
+  fi
+}