Bulk request did not send `cip`

Nobody has claimed this yet.

It seems like tracker-proxy does not include `token_auth` and `cip` in bulk request .
The `X-Forwarded-For` does not work with bulk requests on Matomo 5.

For all bulk requests, the server IP is used on Matomo instead of the real forwarded IP address.

I took some liberty to add a few more methods to the file, it works but I did not test it for PHP < 7.4.

What works:
- Custom events
- Media tracking (Play)

What seems to be broken:
- Media tracking (seeking). (Could it be that the media tracking plugin does not take into account the `cip` passed in the bulk request?)
- Form interaction ( doesn't seem to track, not sure why. I will post here if it works again )

Here's the code:

```php
function isUsingBulkRequest($rawData)
{
if (!empty($rawData)) {
return strpos($rawData, '"requests"') || strpos($rawData, "'requests'");
}

return false;
}

function processBulkQuery($query, $extraParam = []) {
$cleanedQuery = $query;

if (substr($query, 0, 1)) {
$cleanedQuery = substr($query, 1);
}

$parsedQuery = array();
$parsedUrl = parse_str($cleanedQuery, $parsedQuery);

return '?' . http_build_query(array_merge($parsedQuery, $extraParam));
}

function buildAuthBulkRequest($rawData, $auth_token, $cip) {
$jsonData = json_decode($rawData, $assoc = true);
if (!isset($jsonData['requests'])) {
return $rawData;
}
$jsonData['token_auth'] = $auth_token;

$extraQueryParams = [
"cip" => $cip,
];

$jsonData['requests'] = array_map(
function($query) use ($extraQueryParams) {
return processBulkQuery($query, $extraQueryParams);
},
$jsonData['requests']
);

return json_encode($jsonData);
}

````

Add the following code in the POST handler will add `cip` to the individual query and `token_auth` on the post body:

```php
global $TOKEN_AUTH;
$postBody = file_get_contents("php://input");
$isBulk = isUsingBulkRequest($postBody);
...
if($isBulk) {
$stream_options['http']['content'] = buildAuthBulkRequest($postBody, $TOKEN_AUTH, $visitIp);
}
$stream_options['http']['header'][] = "Content-Length: " . strlen($postBody);
```

original requests :

```json
{
"requests": [
"?action=Page",
],
"send_image": 0
}
```

expected result:

```json
{
"requests": [
"?action=Page&cip=0.0.0.0",
],
"send_image": 0,
"token_auth": "TOKEN_AUTH"
}
```

Start by locating the POST handler that reads php://input and forwards tracker requests, then trace how bulk JSON requests are transformed before reaching Matomo 5. Reproduce a bulk request and verify that token_auth is included and cip reaches each individual query, while checking the listed media and form-tracking cases.

Written by the indexing model from the issue text.