fix(shared-state): clear shared Production IDs when input is cleared

Fixes a bug where clearing the order number input in the extraction page
did not clear the shared Production IDs in the main process. This caused
the data cleanup page to continue using stale data when filtering by
Production ID.

Changes:
- Add VALIDATION_CLEAR_SHARED_PRODUCTION_IDS IPC channel
- Register handler to clear shared Production IDs by sender ID
- Expose clearSharedProductionIds API in preload script
- Update ExtractorPage to call clear when order numbers are empty

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/shared/ipc-channels.ts

@@ -51,6 +51,7 @@ export const IPC_CHANNELS = {
   VALIDATION_VALIDATE: 'validation:validate',
   VALIDATION_SET_SHARED_PRODUCTION_IDS: 'validation:setSharedProductionIds',
   VALIDATION_GET_SHARED_PRODUCTION_IDS: 'validation:getSharedProductionIds',
+  VALIDATION_CLEAR_SHARED_PRODUCTION_IDS: 'validation:clearSharedProductionIds',
   VALIDATION_GET_CLEANER_DATA: 'validation:getCleanerData',
 
   // Materials