feat(ui): track last window width ratio on hide

Store the ratio of the output window's width to the total columns when
hiding windows, unless the UI position is 'current'. This enables
restoring window sizes more accurately.

Author: jugarpeupv

lua/opencode/ui/ui.lua

@@ -134,6 +134,12 @@ function M.hide_visible_windows(windows)
 
   local snapshot = capture_hidden_snapshot(windows)
 
+  if config.ui.position ~= 'current' then
+    local total_cols = vim.o.columns
+    local current_width = vim.api.nvim_win_get_width(windows.output_win)
+    state.last_window_width_ratio = current_width / total_cols
+  end
+
   state.clear_hidden_window_state()
 
   prepare_window_close()