Expose Golden Dandelion growth-paused state on EntityAgeableComponent

Since 26.10, using a Golden Dandelion on a baby mob sets its GrowthPaused value to 1 (and back to 0 on a second use). Script API add-ons currently can’t read this state or react when it changes. getDynamicProperty only reads script-written values, and nothing on EntityAgeableComponent exposes the flag.

Requested features (stable @minecraft/server):

1. EntityAgeableComponent.isGrowthPaused: boolean, readable, ideally writable too. This lets scripts detect age-frozen mobs, including ones frozen before the add-on was installed.
2. EntityAgeableComponent.pauseGrowth and resetGrowth as Trigger properties, matching the existing growUp trigger. The entity JSON already has pause_growth and reset_growth event triggers, so the scripting side should mirror them.
3. world.afterEvents.entityGrowthPaused and entityGrowthReset, with entity and the causing player (if any). Scripts could then react without polling.
4. EntityAgeableComponent.getPauseGrowthItems() and getResetGrowthItems(), returning string[], to match getFeedItems() for the new pause_growth_items and reset_growth_items fields.

Use case: My add-on shows particles on age-frozen mobs when a nearby player holds a Golden Dandelion, so players can tell which mobs are frozen. Today I have to mirror the state by listening to playerInteractWithEntity. This breaks for mobs frozen before the pack was installed, and it can drift out of sync with vanilla (for example during the 2-second per-mob cooldown, or when other add-ons pause growth).