feat(slack): add HTTP receiver webhook mode (#1143) - thanks @jdrhyne

Co-authored-by: Jonathan Rhyne <jdrhyne@users.noreply.github.com>

src/config/slack-http-config.test.ts

@@ -0,0 +1,65 @@
+import { describe, expect, it } from "vitest";
+
+import { validateConfigObject } from "./config.js";
+
+describe("Slack HTTP mode config", () => {
+  it("accepts HTTP mode when signing secret is configured", () => {
+    const res = validateConfigObject({
+      channels: {
+        slack: {
+          mode: "http",
+          signingSecret: "secret",
+        },
+      },
+    });
+    expect(res.ok).toBe(true);
+  });
+
+  it("rejects HTTP mode without signing secret", () => {
+    const res = validateConfigObject({
+      channels: {
+        slack: {
+          mode: "http",
+        },
+      },
+    });
+    expect(res.ok).toBe(false);
+    if (!res.ok) {
+      expect(res.issues[0]?.path).toBe("channels.slack.signingSecret");
+    }
+  });
+
+  it("accepts account HTTP mode when base signing secret is set", () => {
+    const res = validateConfigObject({
+      channels: {
+        slack: {
+          signingSecret: "secret",
+          accounts: {
+            ops: {
+              mode: "http",
+            },
+          },
+        },
+      },
+    });
+    expect(res.ok).toBe(true);
+  });
+
+  it("rejects account HTTP mode without signing secret", () => {
+    const res = validateConfigObject({
+      channels: {
+        slack: {
+          accounts: {
+            ops: {
+              mode: "http",
+            },
+          },
+        },
+      },
+    });
+    expect(res.ok).toBe(false);
+    if (!res.ok) {
+      expect(res.issues[0]?.path).toBe("channels.slack.accounts.ops.signingSecret");
+    }
+  });
+});