refactor(config): add dmPolicy aliases for Slack/Discord

src/config/config.dm-policy-alias.test.ts

@@ -0,0 +1,38 @@
+import { describe, expect, it } from "vitest";
+import { validateConfigObject } from "./config.js";
+
+describe("DM policy aliases (Slack/Discord)", () => {
+  it('rejects discord dmPolicy="open" without allowFrom "*"', () => {
+    const res = validateConfigObject({
+      channels: { discord: { dmPolicy: "open", allowFrom: ["123"] } },
+    });
+    expect(res.ok).toBe(false);
+    if (!res.ok) {
+      expect(res.issues[0]?.path).toBe("channels.discord.allowFrom");
+    }
+  });
+
+  it('accepts discord legacy dm.policy="open" with top-level allowFrom alias', () => {
+    const res = validateConfigObject({
+      channels: { discord: { dm: { policy: "open", allowFrom: ["123"] }, allowFrom: ["*"] } },
+    });
+    expect(res.ok).toBe(true);
+  });
+
+  it('rejects slack dmPolicy="open" without allowFrom "*"', () => {
+    const res = validateConfigObject({
+      channels: { slack: { dmPolicy: "open", allowFrom: ["U123"] } },
+    });
+    expect(res.ok).toBe(false);
+    if (!res.ok) {
+      expect(res.issues[0]?.path).toBe("channels.slack.allowFrom");
+    }
+  });
+
+  it('accepts slack legacy dm.policy="open" with top-level allowFrom alias', () => {
+    const res = validateConfigObject({
+      channels: { slack: { dm: { policy: "open", allowFrom: ["U123"] }, allowFrom: ["*"] } },
+    });
+    expect(res.ok).toBe(true);
+  });
+});