* filer: name the read-only path in the write rejection
The write path rejected creates under a read-only rule with a bare
"read only", giving no hint which path was locked or why. Wrap the
error with the matched location prefix and a quota hint so a FUSE
mkdir or S3 put points straight at the offending bucket.
* return the read-only reason over HTTP and drop any query string from the fallback prefix
Chris LuandGitHub
1a19683ee6