Enhance .env.sample and compose.yaml for Versity S3 Gateway by adding detailed comments on NFS metadata handling and sidecar mode. This improves documentation clarity for users configuring NFS mounts and metadata storage options.

komodo/s3/versitygw/compose.yaml

@@ -1,5 +1,9 @@
 # Versity S3 Gateway — POSIX backend over Docker volumes.
 # https://github.com/versity/versitygw
+#
+# POSIX default metadata uses xattrs; NFS often lacks xattr support unless NFSv4.2
+# + client/server support. `--sidecar` stores metadata in files instead (see
+# `posix` flags / VGW_META_SIDECAR in cmd/versitygw/posix.go).
 services:
   versitygw:
     image: versity/versitygw:v1.3.1
@@ -23,12 +27,15 @@ services:
       - /mnt/nfs/versity/s3:/data/s3
       - /mnt/nfs/versity/iam:/data/iam
       - /mnt/nfs/versity/versions:/data/versions
+      - /mnt/nfs/versity/sidecar:/data/sidecar
     command:
       - "--port"
       - ":10000"
       - "--iam-dir"
       - "/data/iam"
       - "posix"
+      - "--sidecar"
+      - "/data/sidecar"
       - "--versioning-dir"
       - "/data/versions"
       - "/data/s3"
@@ -44,8 +51,3 @@ services:
       timeout: 5s
       retries: 3
       start_period: 10s
-
-volumes:
-  s3_data:
-  iam:
-  versions: