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.

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ permissions:
   contents: read
 
 # One matrix, seven platforms: the three Linux-family packaging distros
-# (Debian 12, Fedora 43, Arch), openKylin on x64 and arm64, macOS and
+# (Debian 13, Fedora 43, Arch), openKylin on x64 and arm64, macOS and
 # Windows. The environments match .github/workflows/cd.yml exactly (same
 # container images, same dependency lists, same runner sizes), so a
 # "passes CI, fails CD" dependency drift is caught here first.
@@ -41,7 +41,7 @@ jobs:
             arch: x64
             runner: warp-ubuntu-latest-x64-8x
             triplet: x64-linux
-            container: '{"image":"debian:12","options":"--shm-size=8g"}'
+            container: '{"image":"debian:13","options":"--shm-size=8g"}'
           - name: Fedora
             platform: linux
             distro: fedora
@@ -173,11 +173,11 @@ jobs:
         run: |
           apt-get update
           apt-get install -y \
-            build-essential clang libclang-dev cmake pkg-config nasm \
+            build-essential clang libclang-dev cmake pkgconf nasm \
             git curl zip unzip tar python3 dpkg-dev \
             libpipewire-0.3-dev libspa-0.2-dev libjack-jackd2-dev \
             libasound2-dev libpulse-dev libsndfile1-dev \
-            libgl1-mesa-dev libgl1-mesa-dri mesa-vulkan-drivers \
+            libgl-dev libglvnd-dev libgl1-mesa-dri mesa-vulkan-drivers \
             libvulkan-dev libxkbcommon-dev libxkbcommon-x11-dev xvfb libdrm-dev \
             icc-profiles-free gdb file librsvg2-bin patchelf fonts-dejavu-core \
             autoconf autoconf-archive automake libtool