KUMA 0.2.6 — Optional safety-baseline selection

• Explicit strategy="safety-baseline" validates seven Basic Safety groups,
  then uniformly selects one for one Case and one Run. Versions and catalog
  release come from validated discovery. Missing/ambiguous groups or unsupported
  capabilities fail before a Case POST; no silent fallback or seven-Case batch.
• An explicit Agent Profile group wins. Default auto, disabled automatic
  matching, custom Providers, Judge lifecycle and request recovery are unchanged.
  Use the original request ID for recovery; a new create_run may sample again.
• Documentation now describes actual multipart Evidence metadata, recovery
  headers, current errors and live catalog coordinates. Thanks to @YiWang24 for
  PR #88; integrates the safety-baseline work from PR #62 and README PR #54.
• 显式 strategy="safety-baseline" 验证七个基础安全组后等概率选一个，只生成一个
  Case、返回一个 Run。版本以目录为准；缺组、多版本歧义或能力不足会在 Case POST
  前拒绝，不静默回退、不批量生成七个 Case。Profile 显式选组优先。
• 默认 auto、禁用的自动匹配、custom Provider、Judge 与恢复行为不变。恢复请用
  原请求 ID，重新 create_run 可能重新抽组。文档同步实际 Evidence、错误和目录行为。
• Optional patch from 0.2.5: the new mode is opt-in and defaults do not change.
  Availability follows the official Release/PyPI; no automatic installation.
  这是可选补丁，默认行为不变、不自动安装；是否发布以正式 Release/PyPI 为准。

python -m pip install --upgrade "kuma-defuzex==0.2.6"

Install after the automatic PyPI publication completes. / 自动 PyPI 发布完成后即可安装。

Changes: #90 (integrates #62), #54, #88.