Avoid nested publish OOM in Linux export

tools/build-linux-x64.sh

@@ -7,6 +7,9 @@ project_root="$repo_root/godot"
 export_directory="$repo_root/build/export/linux-x64"
 expected_export_directory="$repo_root/build/export/linux-x64"
 package_directory="$repo_root/build/package"
+managed_publish_directory="$repo_root/build/managed-publish/linux-x64"
+managed_proxy_directory="$repo_root/build/managed-publish-proxy/linux-x64"
+dotnet_proxy_directory="$repo_root/build/dotnet-export-proxy"
 toolchain_root="$repo_root/build/toolchains/godot-4.7-stable-mono-linux-x64"
 xdg_data_home="$toolchain_root/xdg-data"
 
@@ -22,6 +25,55 @@ godot_console="$("$script_dir/bootstrap-godot-linux-x64.sh")"
 ffmpeg_sdk="$("$repo_root/native/age_movie_ffmpeg/bootstrap-linux-x64.sh")"
 "$repo_root/native/age_movie_ffmpeg/build-linux-x64.sh" "$ffmpeg_sdk"
 
+# Godot keeps the editor resident while it launches dotnet publish. On constrained CI runners, that process
+# pair can exceed the job's memory cgroup. Produce the exact ExportRelease/linux-x64 payload first, without
+# compiler/build servers, so the memory-heavy compile and editor stages run sequentially.
+expected_managed_publish_directory="$repo_root/build/managed-publish/linux-x64"
+if [[ "$managed_publish_directory" != "$expected_managed_publish_directory" || "$managed_publish_directory" == "/" ]]; then
+    echo "refusing to replace unexpected managed publish directory: $managed_publish_directory" >&2
+    exit 1
+fi
+rm -rf -- "$managed_publish_directory"
+mkdir -p -- "$managed_publish_directory"
+DOTNET_CLI_USE_MSBUILD_SERVER=0 \
+MSBUILDDISABLENODEREUSE=1 \
+DOTNET_gcServer=0 \
+DOTNET_GCConserveMemory=9 \
+dotnet publish "$project_root/Himegari.csproj" \
+    --configuration ExportRelease \
+    --runtime linux-x64 \
+    --self-contained true \
+    --output "$managed_publish_directory" \
+    -p:GodotTargetPlatform=linuxbsd \
+    -p:UseSharedCompilation=false \
+    -p:BuildInParallel=false \
+    -p:RestoreDisableParallel=true \
+    -p:DebugType=None \
+    -p:DebugSymbols=false
+
+# With dotnet/embed_build_outputs=false, Godot places publish files outside the PCK. Give the editor only the
+# required profile assembly while it creates the real PCK, then stage the complete prepublish after the editor
+# exits. This avoids making the memory-heavy editor traverse/hash the self-contained runtime and FFmpeg bundle.
+expected_managed_proxy_directory="$repo_root/build/managed-publish-proxy/linux-x64"
+if [[ "$managed_proxy_directory" != "$expected_managed_proxy_directory" || "$managed_proxy_directory" == "/" ]]; then
+    echo "refusing to replace unexpected managed proxy directory: $managed_proxy_directory" >&2
+    exit 1
+fi
+rm -rf -- "$managed_proxy_directory"
+mkdir -p -- "$managed_proxy_directory"
+cp -- "$managed_publish_directory/Himegari.dll" "$managed_proxy_directory/Himegari.dll"
+
+real_dotnet="$(command -v dotnet)"
+expected_dotnet_proxy_directory="$repo_root/build/dotnet-export-proxy"
+if [[ "$dotnet_proxy_directory" != "$expected_dotnet_proxy_directory" || "$dotnet_proxy_directory" == "/" ]]; then
+    echo "refusing to replace unexpected dotnet proxy directory: $dotnet_proxy_directory" >&2
+    exit 1
+fi
+rm -rf -- "$dotnet_proxy_directory"
+mkdir -p -- "$dotnet_proxy_directory"
+cp -- "$script_dir/dotnet_publish_proxy.py" "$dotnet_proxy_directory/dotnet"
+chmod +x "$dotnet_proxy_directory/dotnet"
+
 if [[ "$export_directory" != "$expected_export_directory" || "$export_directory" == "/" ]]; then
     echo "refusing to replace unexpected export directory: $export_directory" >&2
     exit 1
@@ -29,9 +81,41 @@ fi
 rm -rf -- "$export_directory"
 mkdir -p -- "$export_directory"
 
+set +e
+DOTNET_CLI_USE_MSBUILD_SERVER=0 \
+MSBUILDDISABLENODEREUSE=1 \
+UseSharedCompilation=false \
+BuildInParallel=false \
+RestoreDisableParallel=true \
+DOTNET_gcServer=0 \
+DOTNET_GCConserveMemory=9 \
+AGE_REAL_DOTNET="$real_dotnet" \
+AGE_PUBLISH_PROJECT="$project_root/Himegari.csproj" \
+AGE_PREPUBLISHED_OUTPUT="$managed_proxy_directory" \
+AGE_PUBLISH_OUTPUT_ROOT="${TMPDIR:-/tmp}/godot-publish-dotnet" \
+AGE_PUBLISH_ASSEMBLY="Himegari.dll" \
+PATH="$dotnet_proxy_directory:$PATH" \
 XDG_DATA_HOME="$xdg_data_home" "$godot_console" \
     --headless --quit-after 120 --path "$project_root" \
     --export-release "Linux x86_64" "$export_directory/Himegari.x86_64"
+export_status=$?
+set -e
+if [[ $export_status -ne 0 ]]; then
+    if [[ $export_status -eq 137 ]]; then
+        echo "Godot export was killed with SIGKILL (137); inspect the runner memory cgroup diagnostics." >&2
+    fi
+    exit "$export_status"
+fi
+
+managed_export_directory="$export_directory/data_Himegari_linuxbsd_x86_64"
+expected_managed_export_directory="$repo_root/build/export/linux-x64/data_Himegari_linuxbsd_x86_64"
+if [[ "$managed_export_directory" != "$expected_managed_export_directory" || "$managed_export_directory" == "/" ]]; then
+    echo "refusing to replace unexpected managed export directory: $managed_export_directory" >&2
+    exit 1
+fi
+rm -rf -- "$managed_export_directory"
+mkdir -p -- "$managed_export_directory"
+cp -a -- "$managed_publish_directory/." "$managed_export_directory/"
 
 python3 -X utf8 "$script_dir/package_linux_x64.py" verify "$export_directory"
 mapfile -t package_outputs < <(