[RPM] Fix broken symlinks when binary name differs from package name & improve asset consistency

[eximius313]

Bug Description
The current RPM packaging logic fails when the application's binary name (defined in linux/CMakeLists.txt) differs from the package name or the pubspec name.

1. Inheritance Issue: MakeRPMConfig extends MakeConfig directly, bypassing the logic in MakeLinuxPackageConfig that parses CMakeLists.txt to find the real BINARY_NAME. As a result, appBinaryName defaults to pubspec.name, causing broken paths if CMake defines a different name.
2. Symlink Issue: The %install script attempts to symlink files using incorrect names, leading to File not found errors during the build or broken symlinks after installation.
3. Builder Inconsistency: AppPackageMakerRPM generates assets (icons, .desktop files) using the project name, but the binary is named differently
4. Metainfo Mismatch: The metainfo logic already used appBinaryName, creating a mix of naming conventions in the BUILD directory.

Proposed Solution

1. Change MakeRPMConfig to extend MakeLinuxPackageConfig. This inherits the correct appBinaryName getter.
2. Update the %install section to create a symlink pointing to the real binary ($appBinaryName) but named after the package (%{name}).
3. Update .png, .desktop, .xml to use appBinaryName