* fix(chat): allow failed turns to be forked
Failed turns can end in Paseo-generated timeline items without provider
message IDs. Anchor forks to canonical timeline positions while retaining
legacy boundaries for compatibility.
Place the fork summary before the new prompt and delimit it as structured
chat history.
* fix(chat): tighten fork boundary handling
* fix(app): focus explicitly opened workspace tabs
Explicit tab navigation could be overwritten by attention-aware workspace
navigation when the visible agent had just finished. Make workspace navigation
own both normal attention selection and explicit targets so callers cannot
sequence them inconsistently.
* test(app): strengthen forked tab focus assertion
* fix(chat): keep attachments visible after creating agents
Agent creation could receive the canonical user message before the client knew the new agent ID. Hand the local rich presentation to that message and preserve it through later timeline hydration.
* refactor(chat): clarify local message presentation naming
* fix(chat): clear pending state after message handoff
