HDDS-13188. Track total pending deletion size for FSO directories in OM via Recon

[tanvipenumudy]

What changes were proposed in this pull request?

The PR extends GET /api/v1/keys/deletePending/dirs/summary endpoint to include totalUnreplicatedDataSize and totalReplicatedDataSize fields for tracking the total pending deletion size for FSO directories in OM.

• totalReplicatedDataSize: Total size of directories pending deletion with expected replicated size.
• totalUnreplicatedDataSize: Total raw size of directories pending deletion without replicated size.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-13188

How was this patch tested?

Manual Testing:

bash-5.1$ ozone sh volume create vol1
bash-5.1$ ozone sh bucket create vol1/buck1 --layout=FILE_SYSTEM_OPTIMIZED
bash-5.1$ ozone fs -mkdir -p ofs://om/vol1/buck1/dir1/dir2/dir3

# Create 1 MB file:
bash-5.1$ dd if=/dev/zero of=test.txt bs=1M count=1
bash-5.1$ ozone fs -put test.txt ofs://om/vol1/buck1/dir1/file1
bash-5.1$ ozone fs -put test.txt ofs://om/vol1/buck1/dir1/dir2/file2
bash-5.1$ ozone fs -put test.txt ofs://om/vol1/buck1/dir1/dir2/dir3/file3

Directory structure:

dir1/
    ├── file1 (1 MB)
    └── dir2/
        ├── file2 (1 MB)
        └── dir3/
            └── file3 (1 MB)

# Recursively delete top-level directory:
bash-5.1$ ozone fs -rm -r ofs://om/vol1/buck1/dir1

GET /api/v1/keys/deletePending/dirs/summary:

Before https://github.com/apache/ozone/pull/8568:

{
  "totalDeletedDirectories": 1,
  "totalReplicatedDataSize": 0,
  "totalUnreplicatedDataSize": 3145728
}

After https://github.com/apache/ozone/pull/8568:

{
  "totalDeletedDirectories": 1,
  "totalReplicatedDataSize": 9437184,
  "totalUnreplicatedDataSize": 3145728
}

[tanvipenumudy]

Closed the current PR, changed the base branch from master to HDDS-13177 on the existing PR: #8591