维护者确认：create_workers 有界并发创建与只读名额快照

## 触发类别

**产品方向**（feat 类型新增功能）

同时命中：
- **规则文档变更**：改到 `docs/dev-rules/orca-team-architecture.md`（审查判据自身变更，需维护者明确确认）
- **架构**：核心路径改动 775 行（≥150）

## 涉及范围

- `packages/maker-core/src/agents/pi/**` 等 Orca 相关核心路径
- 规则文档 `docs/dev-rules/orca-team-architecture.md`

## 维护者确认方式

请在 PR 上直接 **Approve**（确认方向没问题）；如需修改请 **Request Changes**，作者改完后重新 Approve 即放行。

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关联 PR:#2384(作者 @gardenZzz);本 issue 由 review-pr 流程自动创建,用于先讨论该 PR 涉及的产品 / UI 变更,维护者确认后 PR 会恢复推进。

Review PR #2384 and its changes under packages/maker-core/src/agents/pi/**, along with docs/dev-rules/orca-team-architecture.md. Start by checking the proposed bounded-concurrency create_workers behavior and read-only quota snapshot against the stated architecture rules. Done means a maintainer approves the direction or requests changes; this issue is already tied to that PR.

Written by the indexing model from the issue text.