Auto-extract ZIP files in the Inbox

Customers receive document bundles as ZIP archives (e.g. bank exports, client deliverables) and currently have to unzip manually before Filently can process the contents. Requested capability: detect a ZIP dropped into the Filently Inbox folder, extract its contents automatically, then run the normal identify → rename → file pipeline on each extracted file. Open questions to scope: opt-in vs. always-extract, handling of the original archive after extraction (keep/delete/move), and edge cases like nested or password-protected ZIPs.