docs: 同步 README Agent 与 Team 统计 (#182)

## 概述

同步 README 市场摘要与实际目录及 `manifest.json`：

- Agent：5 → 7，补充 `mimo-model-quota-monitor`、`tender-review-assistant`
- Team：1 → 2，补充 `biao-shu-lian-he-shen-cha`
- 将单数 `Team` 调整为复数 `Teams`

## 验证

- `uv run --quiet scripts/catalog/test_validate_catalog_metadata.py`（47
tests passed）
- `uv run --quiet scripts/catalog/validate_catalog_metadata.py
--require-complete`（0 errors）
- README 摘要名称与目录逐项比对通过

README.md

@@ -29,8 +29,8 @@ DesireCore 官方市场仓库，存放官方维护的 Agent/Team/Skill 定义，
 
 The market currently contains:
 
-- `5` Agents: `desirecore`, `dingtalk-workspace`, `feishu-orchestrator`, `invoice-organizer`, `wecom-assistant`
-- `1` Team: `contract-review-team`
+- `7` Agents: `desirecore`, `dingtalk-workspace`, `feishu-orchestrator`, `invoice-organizer`, `mimo-model-quota-monitor`, `tender-review-assistant`, `wecom-assistant`
+- `2` Teams: `biao-shu-lian-he-shen-cha`, `contract-review-team`
 - `40` local built-in skills with `SKILL.md`
 - `31` external skill entries with `entry.json`
 - `71` publishable skills in total (`SKILL.md` + `entry.json`)