[BigDataDZ]

本PR的原始功能修复已进入最新main87c2966：原始修复提交已通过git merge-base --is-ancestor验证，相关核心文件及回归测试已核对。后续MCP运行时调整保留了配置缓存及Origin校验。当前PR头多出的上游同步/基线冲突处理不构成尚未合入的独立功能，因此关闭，避免重复审阅；分支与提交保留。

---

原始说明：
MCP get_snapshot checked artifact ownership but did not reapply the current theme grant or tenantScope. It could return a persisted preview after a user's theme query grant was revoked or when that theme was outside the current request's scope. Before projecting a snapshot, load its persisted parent workspace with the requesting user filter, require its theme, apply current tenantScope and resolve current user/theme permission. Fail closed for missing parents, invalid user IDs or resolver failures. Keep the existing owner check, preview projection and audit handling. Extract authorization/projection into snapshotAccess.js; get_snapshot shrinks to 33 lines, below its 49-line baseline. Four regressions failed before the fix. Tests use real file-backed SQLite, WorkspaceService artifacts, persisted grants, resolveAccessScope and actual SDK handlers on synchronous and async-only paths. They cover narrowed scope, revoked grants, restored authorized preview, different owners, zero user IDs and missing parents; existing preview caps remain intact. Focused 18/18; full suite 744 passed, 15 skipped, 0 failed; eval fixtures 14/14 (two judge results pending). Independent review approved. Architecture errors reduced 32 to 31; no upward baselines. Includes validated prerequisites through #64. Native MySQL persistence acceptance, PostgreSQL/browser acceptance and both Docker configurations passed in CI. The online unit step passed; the job remains red at the existing architecture guard and online eval is skipped. Combined with #65: 748 passed, 15 skipped, 0 failed; architecture errors reduced to 30. 本次邮件/审阅反馈核查后的更新：已合入当前main e19d784，解决上游合并#49–#54后产生的config/size-baseline.json冲突。冲突处理逐项取较低值，未提高任何已有基线；业务代码由Git自动合入。 当前head：db3f7729fab29fb10a73bfa8227a1aea223a7b44。本地定向验证：ℹ tests 51; ℹ pass 49; ℹ fail 0; ℹ skipped 2。跳过项未计为通过。远端CI已重新触发，结果以最新Checks为准，规模门禁尚未宣称全绿。 已再次对齐新发布的main5385ed3（V1.2.0/#76）。逐项保留较低基线，并修复上游基线JSON漏逗号（独立修复#77）；未提高已有数值。当前head：68f7d85f8d9754eea72bc9169251dc68f2ba42bf。本地定向验证：ℹ tests 34; ℹ pass 33; ℹ fail 0; ℹ skipped 1。跳过项未计为通过。 新主分支全量诊断本身有5个失败；此前零失败结果不再代表当前上游。完整CI以最新Checks为准，未宣称全绿。