Closes#631. Closes#804.
Bug A (thinking card below answer / double render / stuck cursor): trailing rAF after 'done'
inserted a duplicate live-turn wrapper into already-settled DOM. Fixed via _streamFinalized flag
+ cancelAnimationFrame in all terminal handlers (done/apperror/cancel/_handleStreamError) +
_scheduleRender guard. All three reported symptoms were the same root cause.
Bug B (accumulator reset): original fix reset assistantText/reasoningText inside _wireSSE on reconnect.
Reverted — server uses one-shot queue.Queue(), no replay on reconnect, reset would wipe valid
pre-drop content causing data loss. Bug A fix alone resolves all symptoms.
#804 (blank page workspace): syncWorkspaceDisplays uses S._profileDefaultWorkspace as fallback;
workspace chip enabled when hasWorkspace (not hasSession); promptNewFile/promptNewFolder/
switchToWorkspace/promptWorkspacePath auto-create session on blank page; boot.js hydrates
_profileDefaultWorkspace from /api/settings before any session exists.
Opus max-effort review + Nathan independent review + full browser QA. 1765/1765 tests.
cancelStream() now clears S.activeStreamId, calls setBusy(false),
setStatus(''), and hides the cancel button directly after the cancel
API request completes. Previously cleanup depended on the SSE 'cancel'
event, which never arrived if the connection was already closed —
leaving 'Cancelling...' status and busy spinner stuck indefinitely.
The SSE cancel handler in messages.js still fires when the connection
is alive and performs additional cleanup (adds 'Task cancelled.' message,
clears tool cards). All operations are idempotent.
9 new tests in tests/test_sprint36.py.
Co-authored-by: Nathan Esquenazi <nesquena@gmail.com>
