Refactor Neo.grid.footer.Toolbar to handle store integration natively.

Changes:

1. Promote Store Logic: Move store_ config and beforeSetStore listener management from DevIndex.view.home.StatusToolbar to Neo.grid.footer.Toolbar.
2. Standardize Listeners: The base class should automatically bind onStoreFilter, onStoreLoad, and onStoreProgress if they are defined on the instance.
3. Refactor StatusToolbar: Update StatusToolbar to rely on the inherited store management.

Benefit: This makes Neo.grid.footer.Toolbar a robust base class for any grid footer requiring store awareness (e.g., PagingToolbar, StatusBars), reducing boilerplate in subclasses.