refactor(chat): drop the Aborted banner from the status surfaces

Aborting a run now just ends it quietly: the status chip and the composer
bar no longer flash an Aborted notice, and the indicator state machine and
its timer are gone from the composer. Acknowledging the session abort
record stays — it is what lets the working chip resume on the next run.

CHANGELOG.md

@@ -4,6 +4,8 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+## [1.21.0] - 2026-08-26
+
 - **Chat scrolling rebuilt around your message.** Sending parks your message near the top and the reply streams in below it, gliding smoothly a paragraph at a time. Scrolling up immediately hands you the wheel; the scroll-to-bottom pill carries the model's working status while you're away.
 - **Keyboard shortcuts redesigned:** single chords for everyday actions, a Cmd/Ctrl+K leader for two-step open/go actions, held Cmd/Ctrl+digit for session tabs and Cmd/Ctrl+Option+digit for panel surfaces. Shortcuts work on non-English keyboard layouts now, tooltips show the binding you actually have set, and old custom bindings reset once. The full map lives in Settings → Shortcuts (registry contributed by @ChangeHow — thanks!).
 - **Chat context attachments:** diff comments, terminal selections, browser annotations, linked issues/PRs and the rest now appear in the conversation as compact context cards instead of walls of raw text.