Pick list failure handling - partial picks, multi-day scenarios

Context

During v1.7.4 planning, we identified edge cases around pick list completion that need separate handling.

Scenarios to Address

1. Partial picking - Load has 10 items, only 7 get picked today. What happens?
2. Multi-day picking - Items picked Monday, truck delayed until Wednesday
3. Pick failure - Item assigned to pick list but unavailable (damaged, can't locate, wrong quantity)
4. Worker reassignment - Worker assigned to pick list but unable to complete (sick, end of shift)

Current Assumption

Loads typically complete same-day. These failure scenarios are deferred for now.

Questions to Answer

• Does load stay in picking status until all items picked?
• Can load transition to loading with partial picks?
• How do we handle items that can't be picked (substitute, cancel, defer)?
• Do we need a staged status between picking and loading?

Related

• v1.7.4 Order/Invoice/Shipment Model milestone
• Pick list feature (future phase)

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Created during v1.7.4 planning discussion