merge: resolve v1.23.0 upstream conflicts, preserve custom git provider config

Resolved conflicts in 8 files by taking upstream refactored code:
- desktop.ts: re-export DesktopSettings from registry
- openchamberConfig.ts: simplified project setup client
- persistence.ts: registry-derived settings, add git provider hydration
- search.ts: upstream search entries + git provider entries
- useConfigStore.ts: loadDesktopSettings() path
- settings-helpers.js: add gitProviderId/gitModelId/gitProviders sanitization
- DOCUMENTATION.md: upstream walkthrough docs
- vite.config.ts: upstream SW glob patterns

Custom fork additions preserved:
- gitProviderId, gitModelId, gitProviders fields in settings registry
- Git provider domain store hydration in persistence.ts
- Git provider search entries in search.ts
- Git provider sanitization in settings-helpers.js

packages/docs/sidebar.config.json

@@ -224,6 +224,22 @@
             "tr": "Proje işlemleri"
           }
         },
+        {
+          "label": "Repository config",
+          "link": "/repository-config/",
+          "translations": {
+            "uk": "Конфіг у репозиторії",
+            "zh-CN": "仓库配置",
+            "es": "Configuración en el repositorio",
+            "pt-BR": "Configuração no repositório",
+            "ko": "저장소 설정",
+            "pl": "Konfiguracja w repozytorium",
+            "fr": "Configuration du dépôt",
+            "ja": "リポジトリ設定",
+            "de": "Repository-Konfiguration",
+            "tr": "Depo yapılandırması"
+          }
+        },
         {
           "label": "Preview & Dev Servers",
           "link": "/preview/",