fix(s6): 恢复 gpustack-server 原始 s6 目录结构，补全 gpustack-server-logger

- producer-for 恢复为目录格式（含 gpustack-server-logger 文件）
- 创建完整的 gpustack-server-logger 目录（type=longrun, run, consumer-for 等）
- 结构与 apiserver/prometheus 等其他 logger 服务保持一致

pack/rootfs/etc/s6-overlay/s6-rc.d/gpustack-server-logger/consumer-for

@@ -0,0 +1 @@
+gpustack-server

pack/rootfs/etc/s6-overlay/s6-rc.d/gpustack-server-logger/pipeline-name

@@ -0,0 +1 @@
+gpustack

pack/rootfs/etc/s6-overlay/s6-rc.d/gpustack-server-logger/run

@@ -0,0 +1,23 @@
+#!/command/with-contenv /bin/bash
+# shellcheck shell=bash
+# shellcheck disable=SC1091,SC1090
+
+SERVICE_DIR=$(cd "$(dirname "$0")" && pwd)
+SERVICE_NAME=$(basename "$SERVICE_DIR")
+SERVICE_NAME=${SERVICE_NAME%-logger}
+
+SCRIPT_ROOT=/etc/s6-overlay/scripts
+source "$SCRIPT_ROOT/base.sh"
+source "$SCRIPT_ROOT/default-variables.sh"
+
+set -e
+
+SERVICE_LOG_DIR="${LOG_DIR}/${SERVICE_NAME}"
+createDir "$SERVICE_LOG_DIR"
+chown 65534:65534 "$SERVICE_LOG_DIR"
+chmod 755 "$SERVICE_LOG_DIR"
+
+# clean leftover lock file
+rm -rf "${SERVICE_LOG_DIR}/lock"
+
+exec logutil-service "${SERVICE_LOG_DIR}"

pack/rootfs/etc/s6-overlay/s6-rc.d/gpustack-server-logger/type

@@ -0,0 +1 @@
+longrun

pack/rootfs/etc/s6-overlay/s6-rc.d/gpustack-server/producer-for

@@ -1 +0,0 @@
-gpustack-server-logger

pack/rootfs/etc/s6-overlay/s6-rc.d/gpustack-server/producer-for/gpustack-server-logger

@@ -0,0 +1 @@
+gpustack-server