fix(line): add ACP binding parity (#56700)

* fix(line): support ACP current-conversation binding

* fix(line): add ACP binding routing parity

* docs(changelog): note LINE ACP parity

* fix(line): accept canonical ACP binding targets

src/channels/thread-bindings-policy.test.ts

@@ -15,6 +15,7 @@ describe("thread binding spawn policy helpers", () => {
   it("allows thread-here on threadless conversation channels without a native thread id", () => {
     expect(requiresNativeThreadContextForThreadHere("telegram")).toBe(false);
     expect(requiresNativeThreadContextForThreadHere("feishu")).toBe(false);
+    expect(requiresNativeThreadContextForThreadHere("line")).toBe(false);
     expect(requiresNativeThreadContextForThreadHere("discord")).toBe(true);
   });
 
@@ -35,5 +36,10 @@ describe("thread binding spawn policy helpers", () => {
         channel: "telegram",
       }),
     ).toBe("current");
+    expect(
+      resolveThreadBindingPlacementForCurrentContext({
+        channel: "line",
+      }),
+    ).toBe("current");
   });
 });

src/channels/thread-bindings-policy.ts

@@ -43,7 +43,7 @@ export function supportsAutomaticThreadBindingSpawn(channel: string): boolean {
 
 export function requiresNativeThreadContextForThreadHere(channel: string): boolean {
   const normalized = normalizeChannelId(channel);
-  return normalized !== "telegram" && normalized !== "feishu";
+  return normalized !== "telegram" && normalized !== "feishu" && normalized !== "line";
 }
 
 export function resolveThreadBindingPlacementForCurrentContext(params: {