feat: add readJsonArrayAs for streaming JSON array files

[buildingvibes]

Summary

Add readJsonArrayAs methods to the zio.json package that read JSON files containing a top-level array and stream each element individually.

This addresses the use case described in #1071 where users need to read JSON files formatted as arrays (e.g. [{"id": 1}, {"id": 2}]) in a streaming fashion, getting a ZStream[Any, Throwable, A] of each decoded element.

Changes

• JsonPackagePlatformSpecific.scala: Added readJsonArrayAs[A: JsonDecoder] overloads for File, Path, String, and URL inputs, following the same pattern as the existing readJsonLinesAs family but using JsonStreamDelimiter.Array instead of JsonStreamDelimiter.Newline.
• DecoderPlatformSpecificSpec.scala: Added tests for reading JSON arrays from both file paths and URLs.
• log.json: Added test resource file containing a JSON array of events.

Usage

import zio.json._

case class Event(at: Long, message: String)
object Event {
  implicit val decoder: JsonDecoder[Event] = DeriveJsonDecoder.gen[Event]
}

// Stream elements from a JSON array file
val events: ZStream[Any, Throwable, Event] =
  readJsonArrayAs[Event](Paths.get("events.json"))

/claim #1071

[buildingvibes]

Hi! Following up on this PR which adds readJsonArrayAs methods (complementing the existing readJsonLinesAs family). All 25+ CI checks pass including the MiMa compatibility check. The implementation is minimal - just 4 new method overloads using JsonStreamDelimiter.Array. Happy to address any feedback!