Changes in version 0.4.0 (2026-11-11)                  

  - Introduced Registry v2 with separate model, provider, interface, and
    capability domains.
  - Refactored llm_caller() into a resolver, request builder, transport,
    response parser, and result-normalization pipeline without changing
    its experiment-facing behavior.
  - Added reusable protocol support for OpenAI-compatible Chat
    Completions, OpenAI Responses, DeepSeek-compatible chat, and
    Anthropic Messages.
  - Added explicit support levels and opt-in production Registry smoke
    tests. OpenAI Responses, DeepSeek Chat/Responses, and Qwen
    Chat/Responses passed live non-stream and stream verification for
    the documented model entries.
  - Preserved Registry v1 user files and the existing public registry
    return structures through compatibility projections.
  - Added network-free contract tests for request construction,
    streaming, response parsing, provider errors, timeouts, secret
    redaction, and bundled Registry v1/v2 equivalence.
  - Added adaptive_feedback_experiment() as the canonical
    adaptive-conversation entry point while preserving
    conversation_experiment_with_feedback() as a backward-compatible
    alias.
  - Corrected experiment result-path handling so an explicit output path
    no longer initializes the default user result directory.
  - Moved automatically named result files to the platform-specific
    package data directory returned by tools::R_user_dir() for
    CRAN-compliant persistence.
  - Added opt-in live DeepSeek coverage for ordinary conversation
    history and bounded adaptive feedback execution.
  - Moved the default user Registry to tools::R_user_dir() while
    retaining read-only compatibility with the historical ~/.psylingllm
    location.
  - Hardened Registry and result persistence so malformed Registry files
    are preserved, v1 registration cannot corrupt v2 bundles, parent
    directories are created explicitly, and failed writes no longer
    report false success.