feat: implement clean Foundry V13 compliant tab system

- Remove custom tab implementation in favor of official ApplicationV2 tabs
- Implement ApplicationTab typedef structure for Actor and Item sheets
- Add memory-safe event listener management with proper cleanup
- Update all sheet templates to use standard Foundry tab structure
- Add template safety checks to prevent undefined access errors
- Optimize performance with DOM updates instead of full re-renders
- Maintain backward CSS compatibility during transition
- Add dynamic tab configuration based on item types

Key improvements:
- ~200 lines of custom tab code removed
- Memory leak prevention with proper event cleanup
- Performance optimization (no re-render on tab switch)
- Standards-compliant with Foundry V13 ApplicationV2 API
- Consistent implementation across Actor and Item sheets
- Template safety with Handlebars guards
- Dynamic icon and localization support

All 31 modified files now use the official Foundry VTT v13 tab system.

templates/sheets/item/tabs/effects.hbs

@@ -4,15 +4,13 @@ SPDX-FileCopyrightText: 2021 Johannes Loher
 SPDX-License-Identifier: MIT
 --}}
 
-<div class="ds4-sheet-tab tab effects" data-group="primary" data-tab="effects">
-    {{#unless (isEmpty enrichedEffects)}}
-    <ol class="ds4-embedded-document-list ds4-embedded-document-list--item-effect effect-list">
-        {{> systems/ds4/templates/sheets/item/components/effect-list-header.hbs}}
-        {{#each enrichedEffects as |effectData id| }}
-        {{> systems/ds4/templates/sheets/item/components/effect-list-entry.hbs effectData=effectData}}
-        {{/each}}
-    </ol>
-    {{/unless}}
-    {{> systems/ds4/templates/sheets/shared/components/add-button.hbs title='DS4.UserInteractionAddEffectTitle'
-    documentType='effect'}}
-</div>
+{{#unless (isEmpty enrichedEffects)}}
+<ol class="ds4-embedded-document-list ds4-embedded-document-list--item-effect effect-list">
+    {{> systems/ds4/templates/sheets/item/components/effect-list-header.hbs}}
+    {{#each enrichedEffects as |effectData id| }}
+    {{> systems/ds4/templates/sheets/item/components/effect-list-entry.hbs effectData=effectData}}
+    {{/each}}
+</ol>
+{{/unless}}
+{{> systems/ds4/templates/sheets/shared/components/add-button.hbs title='DS4.UserInteractionAddEffectTitle'
+documentType='effect'}}