ci/cd: package for Debian 13 instead of Debian 12

The Debian container moves from bookworm to trixie. Two packages were
renamed in trixie and their old names are now transitional dummies:
pkg-config is provided by pkgconf, and libgl1-mesa-dev split into
libgl-dev + libglvnd-dev. The CI and CD Debian dependency lists stay
byte-for-byte identical.

trixie ships libva 2.22, which has the vaMapBuffer2 FFmpeg 8 expects,
so only openKylin still needs the bundled vcpkg libva copies.

docs/build.md

@@ -151,7 +151,7 @@ Distribution packages are built in containers (no host dependencies
 beyond Docker/Podman):
 
 ```sh
-tooling/package/build-deb.sh  # Debian 12  → .deb
+tooling/package/build-deb.sh  # Debian 13  → .deb
 tooling/package/build-rpm.sh  # Fedora 41  → .rpm
 tooling/package/build-pkg.sh  # Arch Linux → .pkg.tar.zst
 ```

docs/zh/build.md

@@ -133,7 +133,7 @@ Windows 构建目标是 **x86_64-pc-windows-gnu**，使用 MSYS2 自带 Rust；
 发行版包在容器中构建（宿主机只需要 Docker/Podman）：
 
 ```sh
-tooling/package/build-deb.sh  # Debian 12  → .deb
+tooling/package/build-deb.sh  # Debian 13  → .deb
 tooling/package/build-rpm.sh  # Fedora 41  → .rpm
 tooling/package/build-pkg.sh  # Arch Linux → .pkg.tar.zst
 ```