Show empty state for BMHomeSectionListView when no items (#452)

[iOSampson]

Title

Show empty state for BMHomeSectionListView when no items (#452)

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Description

Summary:
This pull request adds an empty state to BMHomeSectionListView to handle cases where there are no items available.
Previously, the view appeared as a blank scroll area. With this change, a ContentUnavailableView is displayed instead.

Changes Made:

• Added an emptyView property using ContentUnavailableView with the message “No Available Items.”
• Updated the listView to overlay the empty state when items.isEmpty.
• Used the SF Symbol tray for a minimal and consistent empty state icon.
• Maintained existing layout and styling consistency.

Notes:

• My simulator isn’t currently running, so I wasn’t able to preview the UI in Xcode.
• The implementation should work as expected. It follows SwiftUI’s recommended pattern for ContentUnavailableView.
• Please let me know if any small UI adjustments are needed after testing.