[Paul Lizer (paullizer)]

Summary

• Add a Used Documents mode to the existing chat conversation side pane, sharing the same drawer surface as Conversation Contents.
• Reuse conversation metadata document tags from the details modal so the pane shows cited/used documents and excludes selected-but-unused documents.
• Refresh the document list after streamed grounded responses and auto-open Documents once when cited documents first appear.
• Update feature documentation, release notes, version, and UI coverage.

Validation

• node --check application\single_app\static\js\chat\chat-conversation-details.js
• node --check application\single_app\static\js\chat\chat-conversation-contents.js
• node --check application\single_app\static\js\chat\chat-streaming.js
• python -m pytest ui_tests\test_chat_conversation_contents_drawer.py -q (2 skipped locally because authenticated UI test env vars are not configured)
• git -c core.whitespace=blank-at-eol,blank-at-eof,space-before-tab,cr-at-eol diff --check

Fixes #1209