feat(a0): 完成工程骨架与契约基线

- 建立 pnpm workspace + Turborepo 单仓、ESLint 9/Prettier/commitlint/husky 门禁
- NestJS + Fastify API：统一错误体、trace_id、Zod 管道、/health 真实依赖探活、OpenAPI 3.1 契约
- Prisma 基线：outbox_events/idempotency_keys/system_configs 与首版迁移、幂等种子
- shared 契约包：错误码、权限点、ULID、游标分页、命名/时间工具
- ui 包与 Web 壳层：Semi + Remix 图标统一出口、Cloud Blue 视觉、登录/工作台/错误页
- worker 骨架、Playwright 冒烟、Gitea CI、OpenAPI 快照与 oasdiff 回退脚本
- 补充 A0 实施报告与本地开发说明

scripts/only-allow-pnpm.mjs

@@ -0,0 +1,10 @@
+const userAgent = process.env.npm_config_user_agent ?? '';
+
+if (!userAgent.startsWith('pnpm/')) {
+  console.error('');
+  console.error('✗ 灵犀项目只允许使用 pnpm 10 安装依赖（见 AGENTS.md §3）。');
+  console.error('  请执行：corepack enable && pnpm install');
+  console.error('  或使用：npx pnpm@10.34.9 install');
+  console.error('');
+  process.exit(1);
+}

scripts/openapi-diff.mjs

@@ -0,0 +1,95 @@
+#!/usr/bin/env node
+/**
+ * OpenAPI 兼容性检查（A0 回退实现）。
+ *
+ * 优先使用 oasdiff 二进制；未安装时使用本脚本的结构化回退检查：
+ * - 删除 path / operation
+ * - 删除 components.schemas
+ * - 请求体必填字段新增、字段类型变更
+ *
+ * 基线来自 git HEAD 中的快照；首次提交（快照尚未入库）时跳过。
+ */
+import { execFileSync } from 'node:child_process';
+import { existsSync, readFileSync } from 'node:fs';
+import { resolve } from 'node:path';
+
+const SNAPSHOT = resolve(process.cwd(), 'openapi/lingxi.openapi.json');
+const HTTP_METHODS = ['get', 'post', 'put', 'patch', 'delete', 'head', 'options'];
+
+if (!existsSync(SNAPSHOT)) {
+  console.error(`未找到 OpenAPI 快照：${SNAPSHOT}，请先执行 pnpm openapi:export`);
+  process.exit(1);
+}
+
+const current = JSON.parse(readFileSync(SNAPSHOT, 'utf8'));
+
+let baseline = null;
+try {
+  const raw = execFileSync('git', ['show', `HEAD:${'openapi/lingxi.openapi.json'}`], {
+    encoding: 'utf8',
+    stdio: ['ignore', 'pipe', 'ignore'],
+  });
+  baseline = JSON.parse(raw);
+} catch {
+  console.log('基线快照尚未入库，跳过 OpenAPI diff（首次提交）。');
+  process.exit(0);
+}
+
+const breaking = [];
+
+for (const [path, baselinePath] of Object.entries(baseline.paths ?? {})) {
+  const currentPath = current.paths?.[path];
+  if (!currentPath) {
+    breaking.push(`删除路径：${path}`);
+    continue;
+  }
+  for (const method of HTTP_METHODS) {
+    if (baselinePath[method] !== undefined && currentPath[method] === undefined) {
+      breaking.push(`删除操作：${method.toUpperCase()} ${path}`);
+    }
+  }
+}
+
+for (const schemaName of Object.keys(baseline.components?.schemas ?? {})) {
+  if (current.components?.schemas?.[schemaName] === undefined) {
+    breaking.push(`删除 schema：${schemaName}`);
+  }
+}
+
+const baselineSchemas = baseline.components?.schemas ?? {};
+const currentSchemas = current.components?.schemas ?? {};
+for (const [name, baselineSchema] of Object.entries(baselineSchemas)) {
+  const currentSchema = currentSchemas[name];
+  if (currentSchema === undefined) {
+    continue;
+  }
+  const baselineRequired = new Set(baselineSchema.required ?? []);
+  for (const required of currentSchema.required ?? []) {
+    if (!baselineRequired.has(required)) {
+      breaking.push(`schema ${name} 新增必填字段：${required}`);
+    }
+  }
+  for (const [property, baselineProperty] of Object.entries(baselineSchema.properties ?? {})) {
+    const currentProperty = currentSchema.properties?.[property];
+    if (
+      currentProperty !== undefined &&
+      baselineProperty.type !== undefined &&
+      currentProperty.type !== undefined &&
+      baselineProperty.type !== currentProperty.type
+    ) {
+      breaking.push(
+        `schema ${name}.${property} 类型变更：${baselineProperty.type} -> ${currentProperty.type}`,
+      );
+    }
+  }
+}
+
+if (breaking.length > 0) {
+  console.error('检测到破坏性 OpenAPI 变更：');
+  for (const item of breaking) {
+    console.error(`  - ${item}`);
+  }
+  process.exit(1);
+}
+
+console.log('OpenAPI 无破坏性变更。');