1.1.3

Major updates to FileUpgrader solution

- Updated `.gitignore` to exclude backup and cache files from Advanced Installer.
- Added `_build` project to `FileUpgrader.sln` with unique ID, including solution configurations for R21 to R25.
- Introduced new global sections in `FileUpgrader.sln` for solution properties and a new SolutionGuid.
- Added `build.ps1` PowerShell script for environment setup and build execution.
- Simplified RibbonPanel creation in `App.cs` and updated project SDK in `FileUpgrader.csproj` to `Microsoft.NET.Sdk`.
- Updated package references in `FileUpgrader.csproj`, added `System.Resources.Extensions`, and removed build events.
- Modified `CreateAddinManifest` and `CleanupAddinManifest` targets in `FileUpgrader.csproj`.
- Added launch settings for Revit 2025 and 2024 in `launchSettings.json`.