Refactor project tasks page and navigation components

- Updated the description in ProjectTasksPage to a placeholder.
- Commented out the display of assigned email in ProjectTasksList.
- Removed the dashboard link from the navigation items.
- Changed the main link in the navigation to point to projects instead of the dashboard.
- Commented out the LanguageSwitcher and user role display in the navigation.
- Translated "Project Location" to "Lokalizacja projektu" in ProjectMap.
- Commented out the instruction for using the layer control in ProjectMap.
- Removed the label "Coordinates:" from the coordinates display in ProjectMap.
- Updated project and contract subtitles in translations to placeholders.
- Added a new empty validation schema file.

src/lib/i18n.js

@@ -119,7 +119,7 @@ const translations = {
     // Projects
     projects: {
       title: "Projekty",
-      subtitle: "Zarządzaj swoimi projektami",
+      subtitle: "---",
       newProject: "Nowy projekt",
       editProject: "Edytuj projekt",
       deleteProject: "Usuń projekt",
@@ -162,7 +162,7 @@ const translations = {
     // Contracts
     contracts: {
       title: "Umowy",
-      subtitle: "Zarządzaj swoimi umowami i kontraktami",
+      subtitle: "---",
       newContract: "Nowa umowa",
       editContract: "Edytuj umowę",
       deleteContract: "Usuń umowę",