add duckdb-ui-client & other ts pkgs (#10)

* add duckdb-ui-client & other ts pkgs

* workflow fixes

* fix working dir

* no sparse checkout; specify package.json path

* path to pnpm-lock.yaml

* add check & build test

* workflow step descriptions

* use comments & names

* one more naming tweak

ts/pkgs/duckdb-data-values/test/conversion/jsonFromDuckDBValue.test.ts

@@ -0,0 +1,26 @@
+import { expect, suite, test } from 'vitest';
+import { DuckDBListValue } from '../../src';
+import { jsonFromDuckDBValue } from '../../src/conversion/jsonFromDuckDBValue';
+
+suite('jsonFromDuckDBValue', () => {
+  test('null', () => {
+    expect(jsonFromDuckDBValue(null)).toBe(null);
+  });
+  test('boolean', () => {
+    expect(jsonFromDuckDBValue(true)).toBe(true);
+  });
+  test('number', () => {
+    expect(jsonFromDuckDBValue(42)).toBe(42);
+  });
+  test('bigint', () => {
+    expect(jsonFromDuckDBValue(12345n)).toBe('12345');
+  });
+  test('string', () => {
+    expect(jsonFromDuckDBValue('foo')).toBe('foo');
+  });
+  test('special', () => {
+    expect(jsonFromDuckDBValue(new DuckDBListValue([1, 2, 3]))).toStrictEqual([
+      1, 2, 3,
+    ]);
+  });
+});