Missing event dispatch on product/variant inventory update in Filament resource

[vajdalehel]

• Lunar version: 1.0.0-beta21
• Laravel Version: 12.19.3
• PHP Version: 8.3.22
• Database Driver & Version: MySQL 8.0.42

Expected Behaviour:

When updating product or variant inventory via ManageProductInventory or ManageVariantInventory Filament resources, an event (e.g. ProductUpdated or ProductVariantUpdated) should be dispatched automatically, following the pattern used in other resources.

This would allow these updates to be handled through listeners.

Actual Behaviour:

No event is dispatched when updating via ManageProductInventory or ManageVariantInventory, making it harder to listen for updates.

Steps To Reproduce:

1. Update the stock of a product or variant via the Filament in ManageProductInventory or ManageVariantInventory.

2. Observe that no event is dispatched at all after the update.

3. Compare this behavior to other resource actions (e.g. PriceRelationManager) where a ModelPriceUpdated event is dispatched automatically.

[alecritson]

This will be addressed in #2339