1.3.0 — Cancelled messages are shown as cancelled

Added

• ConversationView now shows a user message that was cancelled before the model produced anything: the bubble is dimmed and captioned “Cancelled — the model won't see this message”, with a matching VoiceOver label. Such a message is dropped from the history sent to the provider on later turns (1.2.0); this makes that visible. The rules live in UserMessagePresentation and are unit-tested (UserMessageRowTests). Hosts that draw their own rows can read ChatSession.UserEntry.isCancelled.
• README “Known limits” section.

Notes

• BalancedEmitterTests is no longer flaky (test-only change, pushed after 1.2.0).