fix(sdk): surface RemoteConversation.fork() title from ConversationInfo

[Zsanz3]

HUMAN:

---

AGENT:

Why

RemoteConversation.fork(title=...) correctly sends title to the agent-server, and ConversationInfo returns title and tags as separate top-level fields. The client only read tags from that response (with a stale comment that tags "include merged title"), so the returned fork object dropped the server-assigned title. The existing unit test mocked that impossible wire shape by putting title inside tags.

Summary

• RemoteConversation.fork() now reads top-level title from the fork ConversationInfo response and stores it on the returned client object.
• Tags remain a separate field; they are no longer treated as if they contain the title.
• test_remote_fork_uses_server_returned_tags mocks title as a top-level field and asserts fork.title.

Issue Number

Fixes #4847

How to Test

uv run pytest tests/sdk/conversation/remote/test_remote_fork.py -v

SDK client-side mapping fix only (no GUI). Live agent-server E2E would need a running remote conversation plus a fork with an explicit title; the contract under test is that the fork response's top-level title is exposed on the returned RemoteConversation.

Test evidence (ran on this branch)

uv run pytest tests/sdk/conversation/remote/test_remote_fork.py -v --tb=short
# all tests in that file PASSED

Type

• Bug fix
• Feature
• Refactor
• Breaking change
• Docs / chore

Notes

Draft until the HUMAN section is filled (≥20 visible characters). Soft claim by @adbcodes had no competing PR at open time.