[Thin Client Integration] Retrieve Thin Proxy Endpoint from Gateway

[kundadebdatta]

Acceptance Criteria:

• The goal of this task is to fetch the thin proxy endpoint from gateway, so that from the .NET sdk side, we could remove the dependency on the hard coded thin proxy endpoint.

• Design and Implement the feature. Update the AccountProperties class to capture the thin proxy endpoint.

Ideally, the GW-SDK contract would look like the below:

{
  "_self": "",
  "id": "sumanttest4-westeurope",
  "_rid": "sumanttest4-westeurope.sql.cosmos.windows-int.net",
  "media": "//media/",
  "addresses": "//addresses/",
  "_dbs": "//dbs/",
  "writableLocations": [
    {
      "name": "West Europe",
      "databaseAccountEndpoint": "[https://sumanttest4-westeurope.documents-test.windows-int.net:443/"](https://sumanttest4-westeurope.documents-test.windows-int.net/%22)
    }
  ],
  "readableLocations": [
    {
      "name": "West Europe",
      "databaseAccountEndpoint": "[https://sumanttest4-westeurope.documents-test.windows-int.net:443/"](https://sumanttest4-westeurope.documents-test.windows-int.net/%22)
    }
  ],
  "enableMultipleWriteLocations": false,
  "continuousBackupEnabled": false,
  "enableNRegionSynchronousCommit": false,
  "userReplicationPolicy": {
    "asyncReplication": false,
    "minReplicaSetSize": 2,
    "maxReplicasetSize": 4
  },
  "userConsistencyPolicy": {
    "defaultConsistencyLevel": "Session"
  },
  "systemReplicationPolicy": {
    "minReplicaSetSize": 3,
    "maxReplicasetSize": 4
  },
  "readPolicy": {
    "primaryReadCoefficient": 1,
    "secondaryReadCoefficient": 1
  },
  "queryEngineConfiguration": "{\"allowNewKeywords\":true,\"maxJoinsPerSqlQuery\":10,\"maxQueryRequestTimeoutFraction\":0.9,\"maxSqlQueryInputLength\":524288,\"maxUdfRefPerSqlQuery\":10,\"queryMaxInMemorySortDocumentCount\":-1000,\"spatialMaxGeometryPointCount\":256,\"sqlAllowNonFiniteNumbers\":false,\"sqlDisableOptimizationFlags\":0,\"sqlQueryILDisableOptimizationFlags\":0,\"clientDisableOptimisticDirectExecution\":false,\"queryEnableFullText\":false,\"enableSpatialIndexing\":true,\"maxInExpressionItemsCount\":2147483647,\"maxLogicalAndPerSqlQuery\":2147483647,\"maxLogicalOrPerSqlQuery\":2147483647,\"maxSpatialQueryCells\":2147483647,\"sqlAllowAggregateFunctions\":true,\"sqlAllowGroupByClause\":true,\"sqlAllowLike\":true,\"sqlAllowSubQuery\":true,\"sqlAllowScalarSubQuery\":true,\"sqlAllowTop\":true}",
  "thinClientWritableLocations": [
    {
      "name": "West Europe",
      "databaseAccountEndpoint": "[https://sumanttest4-westeurope.documents-test.windows-int.net:10650/"](https://sumanttest4-westeurope.documents-test.windows-int.net:10650/%22)
    }
  ],
  "thinClientReadableLocations": [
    {
      "name": "West Europe",
      "databaseAccountEndpoint": "[https://sumanttest4-westeurope.documents-test.windows-int.net:10650/"](https://sumanttest4-westeurope.documents-test.windows-int.net:10650/%22)
    }
  ]
}