Create Upload Stats Service to build response for stats API

[VijayanB]

Description

Add upload stats service to build XContent for StatsNodesResponse. It generates following json as response body

        {
          "uploads": {
            "total": {
                request_count : #of request,
                "upload"       : sum of documents to upload across API,
                "success"     : sum of successfully uploaded documents across API,
                "failed"      : sum of failed to upload documents across API,
                "duration"    : sum of duration in milliseconds to ingest document across API
            },
            "metrics" : [
                {
                    "id"       : <metric-id>,
                    "node_id"  : node-id
                    "upload"   : # of documents to upload,
                    "success"  : # of successfully uploaded documents,
                    "failed"   : # of failed to upload documents,
                    "duration" : duration in milliseconds to ingest document
                }, ......
            ]
          }
        }

Issues Resolved

Check List

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[codecov-commenter]

Codecov Report

Merging #62 (1605eb5) into main (cb1d95d) will increase coverage by 1.02%.
The diff coverage is 100.00%.

❗ Current head 1605eb5 differs from pull request most recent head 315ba7e. Consider uploading reports for the commit 315ba7e to get more accurate results

@@             Coverage Diff              @@
##               main      #62      +/-   ##
============================================
+ Coverage     89.44%   90.46%   +1.02%     
- Complexity      132      144      +12     
============================================
  Files            19       21       +2     
  Lines           483      535      +52     
  Branches         35       38       +3     
============================================
+ Hits            432      484      +52     
  Misses           47       47              
  Partials          4        4              

Impacted Files	Coverage Δ
...arch/geospatial/stats/upload/TotalUploadStats.java	100.00% <100.00%> (ø)
...ch/geospatial/stats/upload/UploadStatsService.java	100.00% <100.00%> (ø)

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[Shivamdhar]

[nit] upload

[VijayanB]

Ack