Transaction Mixin
Done State

Extends mixin.transaction with a done terminal workflow state. Auto-injects the done (finish) button and policy fields into form and list views. Provides the action_done lifecycle handler with pre/post check and pre/post action decorator hook points. The active state key is configurable via the _done_state class attribute.

• Adds done_ok policy field computed automatically for the active user
• Auto-injects the Done button into the form header with inline visibility expression
• Auto-injects Done state badge decorator (success colour) on tree views
• Auto-injects done state filter widget on search views
• Provides action_done with pre/post check and pre/post action decorator hooks
• Posts an automatic chatter notification on finish action
• Configurable sequence creation tied to the done state via _create_sequence_state