feat: Refactor event equipment management with advanced selection and conflict detection

This commit introduces a complete overhaul of how equipment is assigned to events, focusing on an enhanced user experience, advanced selection capabilities, and robust conflict detection.

**Key Features & Enhancements:**

-   **Advanced Equipment Selection UI (`EquipmentSelectionDialog`):**
    -   New full-screen dialog to select equipment and containers ("boîtes") for an event.
    -   Hierarchical view showing containers and a flat list of all individual equipment.
    -   Real-time search and filtering by equipment category.
    -   Side panel summarizing the current selection and providing recommendations for containers based on selected equipment.
    -   Supports quantity selection for consumables and cables.

-   **Conflict Detection & Management (`EventAvailabilityService`):**
    -   A new service (`EventAvailabilityService`) checks for equipment availability against other events based on the selected date range.
    -   The selection dialog visually highlights equipment and containers with scheduling conflicts (e.g., already used, partially unavailable).
    -   A dedicated conflict resolution dialog (`EquipmentConflictDialog`) appears if conflicting items are selected, allowing the user to either remove them or force the assignment.

-   **Integrated Event Form (`EventAssignedEquipmentSection`):**
    -   The event creation/editing form now includes a new section for managing assigned equipment.
    -   It clearly displays assigned containers and standalone equipment, showing the composition of each container.
    -   Integrates the new selection dialog, ensuring all assignments are checked for conflicts before being saved.

-   **Event Preparation & Return Workflow (`EventPreparationPage`):**
    -   New page (`EventPreparationPage`) for managing the check-out (preparation) and check-in (return) of equipment for an event.
    -   Provides a checklist of all assigned equipment.
    -   Users can validate each item, with options to "validate all" or finalize with missing items.
    -   Includes a dialog (`MissingEquipmentDialog`) to handle discrepancies.
    -   Supports tracking returned quantities for consumables.

**Data Model and Other Changes:**

-   The `EventModel` now includes `assignedContainers` to explicitly link containers to an event.
-   `EquipmentAssociatedEventsSection` on the equipment detail page is now functional, displaying current, upcoming, and past events for that item.
-   Added deployment and versioning scripts (`scripts/deploy.js`, `scripts/increment_version.js`, `scripts/toggle_env.js`) to automate the release process.
-   Introduced an application version display in the main drawer (`AppVersion`).

em2rp/deploy.bat

@@ -0,0 +1,60 @@
+@echo off
+REM Script Windows pour incrémenter la version et déployer sur Firebase
+
+echo ================================================
+echo    Déploiement Firebase Hosting avec EM2RP
+echo ================================================
+echo.
+
+echo [0/4] Basculement en mode PRODUCTION...
+node scripts\toggle_env.js prod
+if %ERRORLEVEL% NEQ 0 (
+    echo Erreur lors du basculement en mode production
+    pause
+    exit /b 1
+)
+echo.
+
+echo [1/4] Incrémentation de la version...
+node scripts\increment_version.js
+if %ERRORLEVEL% NEQ 0 (
+    echo Erreur lors de l'incrémentation de la version
+    node scripts\toggle_env.js dev
+    pause
+    exit /b 1
+)
+echo.
+
+echo [2/4] Build Flutter Web...
+call flutter build web --release
+if %ERRORLEVEL% NEQ 0 (
+    echo Erreur lors du build Flutter
+    node scripts\toggle_env.js dev
+    pause
+    exit /b 1
+)
+echo.
+
+echo [3/4] Déploiement Firebase Hosting...
+call firebase deploy --only hosting
+if %ERRORLEVEL% NEQ 0 (
+    echo Erreur lors du déploiement Firebase
+    node scripts\toggle_env.js dev
+    pause
+    exit /b 1
+)
+
+echo.
+echo [4/4] Retour en mode DÉVELOPPEMENT...
+node scripts\toggle_env.js dev
+if %ERRORLEVEL% NEQ 0 (
+    echo ATTENTION: Impossible de rebascule en mode dev
+    echo Exécutez manuellement: node scripts\toggle_env.js dev
+)
+
+echo.
+echo ================================================
+echo    Déploiement terminé avec succès!
+echo ================================================
+pause
+