Phase 0 Complete: Tasks 0.7-0.20

- 0.7: UI-Design-Richtlinien (docs/ui-design-guidelines.md, 535 lines)
- 0.8: Theme-Customization Backend (4 theme fields, migration 0023)
- 0.9: Theme-Customization Frontend (SettingsTheme.tsx, themeStore.ts, live preview)
- 0.10: RBAC-Audit (4 plugins secured, 53 routes with require_permission)
- 0.11: LiteLLM-Cleanup (llm_client.py migrated from httpx to litellm)
- 0.12: KI-Agent-Framework docs (plugin-development-guide.md, agent_capabilities field)
- 0.13: Heartbeat configurable (ProactiveSettings, migration 0024, frontend UI)
- 0.14: Unified Search Field-Level RBAC (resolve_permissions + filter_fields_by_permission)
- 0.15: Undo/History-System (EntityHistory model, service, routes, migration 0025, HistoryViewer)
- 0.16: Storage Backend (LocalStorage + S3Storage, DMS/attachments/mail updated)
- 0.17: Import/Export unified Contact fields (firstname, surname, email_1, phone_1)
- 0.18: .gitignore & Config-Cleanup (webui→frontend, python-jose removed, .env untracked)
- 0.19: Mail-Salt Security-Fix (per-account random salt, migration 0026)
- 0.20: AGPL replaced (PyMuPDF→pypdf, OnlyOffice→Collabora, LICENSE + THIRD_PARTY_LICENSES.md)

frontend/src/i18n/locales/en.json

@@ -261,7 +261,29 @@
     "pluginUninstalledSuccess": "Plugin uninstalled successfully.",
     "pluginUninstallConfirm": "Really uninstall plugin",
     "pluginRemoveData": "Also remove plugin data (tables)",
-    "roleDeleted": "Role deleted successfully."
+    "roleDeleted": "Role deleted successfully.",
+    "themeTitle": "Theme Customization",
+    "themeDescription": "Customize colors, font, and appearance.",
+    "themeSaved": "Theme saved",
+    "themeSaveError": "Failed to save theme",
+    "unsavedChanges": "Unsaved changes",
+    "presets": "Presets",
+    "presetsDescription": "Quickly choose a color palette",
+    "colors": "Colors",
+    "colorsDescription": "Customize primary and accent colors",
+    "primaryColor": "Primary color",
+    "accentColor": "Accent color",
+    "typography": "Typography & Layout",
+    "fontFamily": "Font family",
+    "borderRadius": "Border radius",
+    "darkMode": "Dark Mode",
+    "darkModeDescription": "Switch between light and dark theme",
+    "darkModeOn": "Dark theme active",
+    "darkModeOff": "Light theme active",
+    "livePreview": "Live Preview",
+    "livePreviewDescription": "This is how the app looks with the current theme",
+    "resetTheme": "Reset",
+    "saveTheme": "Save theme"
   },
   "auditLog": {
     "title": "Audit Log",
@@ -857,5 +879,17 @@
     "addTag": "Add tag",
     "create": "New tag",
     "selectTags": "Select {{count}} tags"
+  },
+  "history": {
+    "title": "Change History",
+    "undo": "Undo",
+    "undone": "Action undone",
+    "undoError": "Undo failed",
+    "restore": "Restore this version",
+    "restored": "Version restored",
+    "restoreError": "Restore failed",
+    "empty": "No change history available",
+    "changes": "Changes",
+    "fieldsChanged": "fields changed"
   }
-}
+}