fix: resolve 273 module import errors in frontend build

- Create backward-compatible UI component re-exports (button.ts, card.ts, etc.)
- Add ScrollArea component using MUI Box with custom scrollbar styling
- Add Sonner-compatible toast API using MUI Snackbar/Alert
- Fix schema-types imports to use @/lib/schema-types alias
- Fix incorrect relative import paths in auth, packages, password modules
- Fix page-renderer imports for database and lua-engine
- Remove tailwind-merge dependency (project uses MUI)
- Install missing @phosphor-icons/react package
- Create accordion.ts re-export shim

Reduced TypeScript errors from 409 to 136 - remaining errors are
MUI component prop type mismatches requiring API adjustments.

dbal/ts/tests/core/validation/validate-package-create.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it } from 'vitest'
+import { validatePackageCreate } from '../../../src/core/validation/validate-package-create'
+
+describe('validatePackageCreate', () => {
+  const base = {
+    name: 'forum',
+    version: '1.0.0',
+    author: 'MetaBuilder',
+    manifest: { dependencies: [] },
+    isInstalled: false,
+  }
+
+  it.each([
+    { data: base, expected: [] },
+    { data: { ...base, installedAt: '2024-01-01T00:00:00Z' }, expected: [] },
+  ])('returns $expected for valid case', ({ data, expected }) => {
+    expect(validatePackageCreate(data)).toEqual(expected)
+  })
+
+  it.each([
+    { data: { ...base, version: '1.0' }, message: 'version must be semantic (x.y.z)' },
+    { data: { ...base, manifest: [] }, message: 'manifest must be an object' },
+    { data: { ...base, isInstalled: 'no' as unknown as boolean }, message: 'isInstalled must be a boolean' },
+    { data: { ...base, installedBy: 'invalid' }, message: 'installedBy must be a valid UUID' },
+  ])('rejects invalid case', ({ data, message }) => {
+    expect(validatePackageCreate(data)).toContain(message)
+  })
+})