fix(chat): match main timer and task placement

Restore the completed work timer divider and text size from main. Keep todo-list progress in the composer and omit it from web and mobile timeline entries, including completed task lists.

Verified pending, running, and completed task projection; 187 focused web tests and 35 mobile tests pass. Web and mobile typechecks pass.
e1898cf13dJulius Marminge committed on 9/5/2026, 4:54:30 AMparent6502e22
7 files changedLine totals unavailable