fix(init): tighten dirty-buffer warning message

lua/pending/init.lua

@@ -87,7 +87,7 @@ end
 local function require_saved()
   local bufnr = buffer.bufnr()
   if bufnr and vim.bo[bufnr].modified then
-    log.warn('Buffer has unsaved changes — write with :w first.')
+    log.warn('save changes first (:w)')
     return false
   end
   return true