refactor: standardize event patterns in entity edit dialogs

[Flo0806]

Description

The entity tab components in edit dialogs use two different event patterns inconsistently. This should be standardized for better maintainability.

Current State

Pattern A: @changed event (component manages everything internally)

Used by: EntityLocationsTab, EntityPlayersTab, EntityFactionsTab

• Component handles add/update/remove internally
• Emits single @changed event
• Parent just calls loadCounts() or refresh*()

Pattern B: @add/@remove/@update events (parent manages logic)

Used by: NpcRelationsTab, NpcMembershipsTab, EntityItemsTab, EntityLoreTab, EntityNpcsTab

• Component emits granular events
• Parent handles API calls and state updates
• Parent calls loadCounts() after each operation

Recommendation

Standardize on Pattern A (@changed) because:

1. Better encapsulation - component is self-contained
2. Less boilerplate in parent dialogs
3. Easier to maintain and test
4. Parent doesn't need to know internal implementation details

Affected Components

Components to refactor to Pattern A:

• EntityItemsTab.vue
• EntityLoreTab.vue
• EntityNpcsTab.vue
• NpcRelationsTab.vue
• NpcMembershipsTab.vue

Implementation

For each component:

1. Move API calls from parent into component
2. Add internal state management
3. Replace @add/@remove/@update with single @changed emit
4. Update all parent dialogs to use @changed