fix(docs): exclude v1 migration fields from schema coverage

[eetoc]

Summary

• exclude temporary AgentSpec.display_name, AgentSpec.description, scheduler presentation metadata, and WorkspaceSpec.commit from public YAML schema coverage
• scope compatibility exclusions by Go struct and YAML field so future fields with the same YAML name still require documentation
• add a focused regression test for the schema coverage filter

Testing

• npm test (in tools/genpages)
• task docs:build --force
• git diff --check

Checklist

• Documentation coverage remains aligned with the public v2 authoring surface.
• Tests added or updated for changed behavior.
• No generated build/pages files committed.
• No secrets, private endpoints, or local runtime state included.

[monkeyscan]

PR Title: fix(docs): exclude v1 migration fields from schema...

Commit: 4236b66

本次 PR 对 schema 覆盖率工具进行了两处核心修改：

1. 字段排除粒度从全局改为类型级别：documentedYAMLSchemaFields 函数不再简单地全局排除 description、display_name 等字段，而是通过正则匹配 type X struct { ... } 结构，按 ${TypeName}.${field} 的形式精确排除。这样可以避免误伤其他类型中同名的合法字段。

2. 新增 WorkspaceSpec.commit 到 v1 迁移兼容排除列表：对应从文档中移除 workspace 的 commit 字段说明，并同步更新了中英文文档。

3. 测试更新：测试用例重构为包含 AgentSpec、WorkspaceSpec、ReleaseSpec 三个结构体，验证 WorkspaceSpec.commit 被排除的同时 ReleaseSpec.commit 仍被保留。

整体评估：变更目标明确，实现逻辑正确，测试覆盖了核心场景，文档与代码保持一致。正则 type\s+(\w+)\s+struct\s*\{([\s\S]*?)\n\} 在标准 Go 代码格式下能正确工作，未发现引入的行为回归或严重缺陷。

[innomentats]

LGTM