Extract package versions into a single versions.sh file

All hardcoded versions are now defined once in versions.sh and sourced
by build-toolchain.sh, download_prerequisites.sh, and build-libraries.sh,
eliminating the need to update multiple files when changing a version.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

download_prerequisites.sh

@@ -1,5 +1,7 @@
 #!/bin/bash
 
+source "$(dirname "$0")/versions.sh"
+
 # Создаем папки для исходников
 mkdir -p src/toolchain src/libs
 
@@ -32,18 +34,18 @@ download_files() {
 
 # Исходники тулчейна
 toolchain_files=(
-    "https://ftp.gnu.org/gnu/binutils/binutils-2.42.tar.xz"
-    "https://ftp.gnu.org/gnu/gcc/gcc-13.4.0/gcc-13.4.0.tar.xz"
-    "https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.9.224.tar.xz"
-    "https://downloads.uclibc-ng.org/releases/1.0.55/uClibc-ng-1.0.55.tar.xz"
+    "https://ftp.gnu.org/gnu/binutils/binutils-${BINUTILS_VER}.tar.xz"
+    "https://ftp.gnu.org/gnu/gcc/gcc-${GCC_VER}/gcc-${GCC_VER}.tar.xz"
+    "https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-${LINUX_VER}.tar.xz"
+    "https://downloads.uclibc-ng.org/releases/${UCLIBC_VER}/uClibc-ng-${UCLIBC_VER}.tar.xz"
 )
 
 # Исходники библиотек
 libs_files=(
-    "https://download.savannah.gnu.org/releases/freetype/freetype-2.13.2.tar.gz"
-    "https://github.com/LibVNC/libvncserver/archive/LibVNCServer-0.9.14.tar.gz"
-    "https://www.openssl.org/source/openssl-3.0.13.tar.gz"
-    "https://zlib.net/fossils/zlib-1.2.13.tar.gz"
+    "https://download.savannah.gnu.org/releases/freetype/freetype-${FREETYPE_VER}.tar.gz"
+    "https://github.com/LibVNC/libvncserver/archive/LibVNCServer-${LIBVNCSERVER_VER}.tar.gz"
+    "https://www.openssl.org/source/openssl-${OPENSSL_VER}.tar.gz"
+    "https://zlib.net/fossils/zlib-${ZLIB_VER}.tar.gz"
 )
 
 echo "=== Загрузка исходников тулчейна в 'src/toolchain' ==="