Add NATS account-balance SoT and statement review for customers, CS, and sales

Internal billing now uses verae.billing.* request-reply and pubs. zappier-account-balance tracks prepaid, credits, usage, and payments. Portal, admin, CS, and sales all review the same statement. Independent Forgejo repos stay split via push-module-repos.

packages/zappier-account-balance/test/health.test.js

@@ -0,0 +1,30 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { spawn } from 'node:child_process';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const root = path.join(path.dirname(fileURLToPath(import.meta.url)), '..');
+
+test('account-balance health and statement', async () => {
+  const port = 18010;
+  const child = spawn(process.execPath, ['src/server.js'], {
+    cwd: root,
+    env: { ...process.env, PORT: String(port) },
+    stdio: ['ignore', 'pipe', 'pipe'],
+  });
+  await new Promise((r) => setTimeout(r, 400));
+  try {
+    const h = await (await fetch(`http://127.0.0.1:${port}/health`)).json();
+    assert.equal(h.role, 'zappier-account-balance');
+    await fetch(`http://127.0.0.1:${port}/adjust`, {
+      method: 'POST',
+      headers: { 'content-type': 'application/json' },
+      body: JSON.stringify({ customerId: 'c1', cents: 200, reason: 'test' }),
+    });
+    const st = await (await fetch(`http://127.0.0.1:${port}/statement/c1`)).json();
+    assert.equal(st.prepaidCents, 200);
+  } finally {
+    child.kill('SIGTERM');
+  }
+});