feat(matrix): thread-isolated sessions and per-chat-type threadReplies (#57995)

Merged via squash.

Prepared head SHA: 9ed96dd063
Co-authored-by: teconomix <6959299+teconomix@users.noreply.github.com>
Co-authored-by: gumadeiras <5599352+gumadeiras@users.noreply.github.com>
Reviewed-by: @gumadeiras

src/config/sessions/delivery-info.test.ts

@@ -44,6 +44,14 @@ describe("extractDeliveryInfo", () => {
       baseSessionKey: "agent:main:slack:channel:C1",
       threadId: "123.456",
     });
+    expect(
+      parseSessionThreadInfo(
+        "agent:main:matrix:channel:!room:example.org:thread:$AbC123:example.org",
+      ),
+    ).toEqual({
+      baseSessionKey: "agent:main:matrix:channel:!room:example.org",
+      threadId: "$AbC123:example.org",
+    });
     expect(parseSessionThreadInfo("agent:main:telegram:dm:user-1")).toEqual({
       baseSessionKey: "agent:main:telegram:dm:user-1",
       threadId: undefined,