feat: OPC 工作台 — 科普（慰心斋）单项目管理系统

Flask + Tailwind CSS + Trix + Chart.js + Lucide Icons + SQLite

- 首页概览：关键指标卡片、财务趋势图、风险提醒、近期动态
- 销售管理：客户表格 + 抽屉详情（自动保存 + 评论）
- 业务方案：版本表格 + 抽屉（文件上传/预览/删除 + 评论）
- 运营管理：项目表格（业务机会/执行项目分类）+ 抽屉
- 产品研发：版本表格 + 抽屉
- 财务管理：月度收入/毛利/成本/净利曲线图 + 明细表
- 所有抽屉：Plane 风格紧凑布局、字段失焦自动保存、Trix 富文本评论框、点击遮罩关闭

docs/design-system-summary.md

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+# OPC Manager Design System Summary
+
+Project: 科普（慰心斋）OPC 工作台  
+Purpose: single-project operating dashboard for sales, business proposals, operations, product versions, and finance.
+
+## Design Direction
+
+- Style: enterprise operations dashboard, not a marketing landing page.
+- Priority: clarity, scan speed, table density, stable editing flows.
+- Primary color: calm blue for navigation and primary actions.
+- Status colors: red for risk, amber for pending, green for completed, slate for archived.
+- Surface system: white content surfaces on a light slate background, thin borders, compact spacing.
+
+## Layout Rules
+
+- Default view is the overview dashboard.
+- Use top tabs for primary modules.
+- Use tables for sales and operations.
+- Use cards only for repeated version entities: business proposals and product versions.
+- Use right-side drawers for editable details.
+- Use Recharts line charts for finance trends, with detail tables below.
+
+## Component Rules
+
+- Tables should fit meeting review scenarios: compact rows, visible status badges, latest activity.
+- Drawers should contain editable fields and timelines without navigating away.
+- File groups should show category, file name, preview, download, and upload affordances.
+- Charts must use the same data as detail tables.
+