refactor: unify channel config matching and gating

Co-authored-by: thewilloftheshadow <thewilloftheshadow@users.noreply.github.com>

src/channels/channel-config.test.ts

@@ -1,6 +1,10 @@
 import { describe, expect, it } from "vitest";
 
-import { buildChannelKeyCandidates, resolveChannelEntryMatch } from "./channel-config.js";
+import {
+  buildChannelKeyCandidates,
+  resolveChannelEntryMatch,
+  resolveChannelEntryMatchWithFallback,
+} from "./channel-config.js";
 
 describe("buildChannelKeyCandidates", () => {
   it("dedupes and trims keys", () => {
@@ -22,3 +26,44 @@ describe("resolveChannelEntryMatch", () => {
     expect(match.wildcardKey).toBe("*");
   });
 });
+
+describe("resolveChannelEntryMatchWithFallback", () => {
+  it("prefers direct matches over parent and wildcard", () => {
+    const entries = { a: { allow: true }, parent: { allow: false }, "*": { allow: false } };
+    const match = resolveChannelEntryMatchWithFallback({
+      entries,
+      keys: ["a"],
+      parentKeys: ["parent"],
+      wildcardKey: "*",
+    });
+    expect(match.entry).toBe(entries.a);
+    expect(match.matchSource).toBe("direct");
+    expect(match.matchKey).toBe("a");
+  });
+
+  it("falls back to parent when direct misses", () => {
+    const entries = { parent: { allow: false }, "*": { allow: true } };
+    const match = resolveChannelEntryMatchWithFallback({
+      entries,
+      keys: ["missing"],
+      parentKeys: ["parent"],
+      wildcardKey: "*",
+    });
+    expect(match.entry).toBe(entries.parent);
+    expect(match.matchSource).toBe("parent");
+    expect(match.matchKey).toBe("parent");
+  });
+
+  it("falls back to wildcard when no direct or parent match", () => {
+    const entries = { "*": { allow: true } };
+    const match = resolveChannelEntryMatchWithFallback({
+      entries,
+      keys: ["missing"],
+      parentKeys: ["still-missing"],
+      wildcardKey: "*",
+    });
+    expect(match.entry).toBe(entries["*"]);
+    expect(match.matchSource).toBe("wildcard");
+    expect(match.matchKey).toBe("*");
+  });
+});