Update CHANGELOG for 1.2.0 release (#21)

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: jkebinger

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## [1.2.0] - 2026-01-22
+
+- Add SSE watchdog to detect stuck connections and trigger recovery via polling fallback [#20]
+- Fix 401/403 handling in SSE streaming loop - now properly catches HTTPError instead of unreachable UnauthorizedException [#20]
+- Fix silent SSE loop exits by catching BaseException and adding finally block logging [#20]
+- Ensure streaming starts even when checkpoint loading fails, allowing SSE to recover [#20]
+- Pin Poetry version to 1.8.5 in CI workflows to fix installation failures [#20]
+
 ## [1.1.1] - 2025-11-20
 
 - Fix InternalLogger to properly register with Python's logging hierarchy, enabling handler propagation from `logging.basicConfig()` and parent loggers [#18]