Version 1.0.0

First stable release of the Market Data Java & Kotlin SDK — a single JVM
artifact, idiomatic from both Java and Kotlin, covering the full v1 API surface
with sync + async parity on every endpoint.

Added

• MarketDataClient — no-arg constructor (everything resolved from the
  configuration cascade) and a 4-arg constructor for tests/short-lived runtimes.
  Single shared HttpClient (HTTP/2), 99 s request / 2 s connect timeouts,
  close() for resource release, and getRateLimits().
• Configuration cascade — explicit constructor parameters → MARKETDATA_*
  environment variables → .env in the working directory → built-in defaults.
  baseUrl / apiVersion are normalized and validated at construction.
• Demo mode — without a token the client omits the Authorization header
  and serves public, read-only endpoints; validateOnStartup verifies auth on
  construction otherwise.
• Options resource (client.options()) — lookup, expirations,
  strikes, quote, quotes (per-symbol fan-out map), and chain with the
  full filter surface (sealed ExpirationFilter / StrikeFilter, greeks,
  expiration=all, countback).
• Stocks resource (client.stocks()) — candles, quote, quotes and
  prices (batched multi-symbol), news, and earnings. StockResolution
  value type for open-ended resolutions; intraday windows over ~1 year are
  auto-split, fetched concurrently, and merged.
• Markets resource (client.markets()) — status, the exchange
  open/closed calendar with date / from-to / countback windowing and
  country selection.
• Funds resource (client.funds()) — candles, NAV OHLC series at
  daily-and-up resolutions (FundResolution).
• Utilities resource (client.utilities()) — service status and auth
  validation.
• Universal parameters & formats — dateFormat / mode / limit /
  offset / columns set fluently on every resource (immutable configured
  copies), plus an asCsv() facet (with human / headers shaping) for every
  endpoint. columns projection enforces the Option A strict-decoding contract.
• Reliability — retry with exponential backoff (4 total attempts,
  Retry-After honored), client-level and per-response rate-limit snapshots
  with preflight, /status/ stale-while-revalidate cache gating retries, and a
  50-permit async concurrency pool.
• Sealed MarketDataException hierarchy — seven canonical subtypes
  (AuthenticationError, BadRequestError, NotFoundError, RateLimitError,
  ServerError, NetworkError, ParseError), each carrying support context
  (requestId, requestUrl, statusCode, timestamp) and getSupportInfo().
• First-class Kotlin interop — @NullMarked (JSpecify) on every public
  package, no Kotlin-stdlib or coroutines runtime dependency, SAM callbacks, and
  Kotlin-reserved-word-free public API.
• Packaging — MIT license, SemVer, version auto-detected from the JAR
  manifest, published to Maven Central as app.marketdata:marketdata-sdk-java.