feat: prepare ARR for controlled public deployment

.project-docs/10-decisions/decision-index.md

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+# Decision Index
+
+## Active Decisions
+
+| ID | Decision | Status | Date | Applies To | Detail |
+|---|---|---|---|---|---|
+| ADR-001 | 月报在 Agent 结构化结果成功入库后由业务系统自动触发；`TOTAL PRICE` 为 Excel 公式字段 | Accepted | 2026-07-29 | 上传链路、月报触发、XLSX 输出 | [ADR-001](ADR-001-automatic-monthly-trigger-and-total-price-formula.md) |
+
+## Superseded Decisions
+
+| ID | Decision | Superseded By | Date |
+|---|---|---|---|
+| Conversation draft | 用户点击月报按钮并提交或选择年月/截止范围；金额写静态值 | ADR-001 | 2026-07-29 |
+
+## Decision Criteria
+
+Create or update an ADR when a choice affects:
+
+- project positioning
+- architecture boundaries
+- public behavior
+- data model
+- long-term maintenance
+- user-facing workflow