feat: add direct PostgreSQL and ACK deployment support

tests/database-readiness-contract.test.ts

@@ -0,0 +1,25 @@
+import { readFile } from "node:fs/promises";
+import { describe, expect, it } from "vitest";
+
+describe("PostgreSQL readiness contract", () => {
+  it("checks every runtime table and both atomic functions", async () => {
+    const source = await readFile(new URL("../lib/server/database.ts", import.meta.url), "utf8");
+    for (const table of [
+      "assets",
+      "generation_jobs",
+      "usage_events",
+      "projects",
+      "image_templates",
+      "platform_organizations",
+      "platform_users",
+      "platform_account_migrations",
+      "billing_price_rules",
+      "billing_wallets",
+      "billing_ledger"
+    ]) {
+      expect(source).toContain(`('${table}',`);
+    }
+    expect(source).toContain("claim_generation_jobs(text,integer,integer)");
+    expect(source).toContain("billing_post_wallet_entry(text,text,text,text,text,bigint,text,text,text,jsonb)");
+  });
+});