missing fields

in Ahiqar project we want to migrate to SearchAPI but we are missing some keys.

• fine-grained hit counts:
  • occurrencesOnPage for how many hits we get on a single page
    • this might become kwic.length(), as far as kwics are not paginated or truncated
  • more info within total
• indices giving the index number of the manifest and item to target = TIDO bookmark URL

here is a sample query returning a single hit (page): UI: https://ahiqar.uni-goettingen.de/search.html?searchTerm=%DC%98%DC%9A%DC%BF%DC%A2%DC%A9&page=1

curl 'https://api.ahiqar.uni-goettingen.de/search' -X POST --data-raw $'{"query":{"simple_query_string":{"query":"\u0718\u071a\u073f\u0722\u0729"}},"from":0,"size":5}'

{
  "request" : "{\"query\":{\"simple_query_string\":{\"query\":\"ܘܚܿܢܩ\"}},\"from\":0,\"size\":5}",
  "took" : 0.015,
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq",
      "manifests" : 1,
      "matches" : 1
    },
    "hits" : [ {
      "type" : "transcription",
      "lang" : "syc",
      "label" : "Paris, Bibliothèque Nationale de France, ms. syr. 434",
      "n" : "186v",
      "item" : "https://api.ahiqar.sub.uni-goettingen.de/textapi/ahiqar/syriac/3r678/186v/latest/item.json",
      "indices" : "m0_i0",
      "matches" : [ {
        "match" : "ܘܚܿܢܩ",
        "occurrencesOnPage" : 1
      } ]
    } ]
  }
}

/cc @schaefer49 @uveentj