v3.0.2

A single batch can now safely mix sub-requests that return any
Content-Type (JSON, problem+json, vendor +json, HTML, text, XML/SVG,
PDF, PNG, octet-stream, BinaryFileResponse, StreamedResponse, 204).
Previously binary bodies corrupted the outer JsonResponse envelope and
BinaryFileResponse/StreamedResponse payloads were silently dropped.

Changes

• New Lemric\BatchRequest\Bridge\ResponseFormatter (framework-agnostic,
  shared by both bridges — works for Laravel too because
  Illuminate\Http\Response extends Symfony's and Laravel reuses
  Symfony's BinaryFileResponse/StreamedResponse).

  • JSON / */*+json → decoded array.
  • text/* and application/{xml,*+xml,javascript,yaml,…} → raw string.
  • Anything else → base64-encoded body + body_encoding: "base64".
  • BinaryFileResponse materialised via getFile().
  • StreamedResponse captured via output buffering.
  • Malformed JSON with a JSON content type stays as raw string
    (server claimed text, no base64).
  • Empty/no-content responses return "" (consistent string typing).

• Symfony/SymfonyTransactionExecutor and
  Laravel/LaravelTransactionExecutor delegate response shaping to the
  new formatter; duplicated formatResponse/extractHeaders/
  isJsonContentType removed.

• README: new "Mixed content types in a single batch" section with the
  Content-Type → body-shape table and an example mixed response.

Tests

• New tests/Bridge/ResponseFormatterTest.php (17 cases) covers every
  branch and a mixed-batch round-trip through json_encode.
• New tests/Bridge/ResponseFormatterLaravelTest.php (9 cases) proves
  the formatter handles Illuminate\Http\{Response,JsonResponse} and
  Symfony BinaryFileResponse/StreamedResponse returned by Laravel
  helpers.
• SymfonyTransactionExecutorTest::testExecuteHandlesResponseWithoutContent
  updated: empty body is now "" instead of [].