feat: initialize ERP base platform (extracted from HMS)

- Stripped 11 business crates (health, ai, dialysis, plugins)
- Cleaned AppState, AppConfig, main.rs from business coupling
- Reduced migrations from 169 to 53 (base-only)
- Removed health_provider trait from erp-core
- Removed business integration tests
- Removed gateway rate limiting middleware
- Base capabilities: auth, RBAC, JWT, config, workflow, message, plugin, audit, crypto, RLS, multi-tenant

Cargo check: OK
Cargo test: OK

apps/web/e2e/plugins.spec.ts

@@ -0,0 +1,24 @@
+import { test, expect } from './auth.fixture';
+
+test.describe('插件管理', () => {
+  test('插件管理页面加载', async ({ page }) => {
+    await page.goto('/#/');
+    // 侧边栏显示"扩展管理插件管理"
+    await page.locator('text=扩展管理').first().click();
+    await page.waitForLoadState('networkidle');
+    // 页面不崩溃
+    await expect(page.locator('main')).toBeVisible();
+  });
+
+  test('刷新按钮可点击', async ({ page }) => {
+    await page.goto('/#/');
+    await page.locator('text=扩展管理').first().click();
+    await page.waitForLoadState('networkidle');
+    const refreshBtn = page.locator('button:has-text("刷新")');
+    if (await refreshBtn.isVisible().catch(() => false)) {
+      await expect(refreshBtn).toBeEnabled();
+      await refreshBtn.click();
+      await expect(page.locator('main')).toBeVisible();
+    }
+  });
+});