dropthejase polishes the chat surface

doc_read_start emits real filename; afterToolCallEvent was emitting
filename from result.filename which is always empty (read_document
returns plain text not JSON). Now looks up filename from docIndex
using the tool input doc_id, matching what the start event used.

Both ChatView and ProjectChatPage now use MessageList. Edit resolution state
(resolvedEditStatuses, reloadingEditIds) lives in MessageList - ProjectChatPage
no longer has a no-op handleEditResolved stub, so Accept/Reject cards now
collapse correctly in Project Chat.

- EditCard returns null when resolved (accepted or rejected)
- EditCardsSection auto-collapses via useEffect when all pending edits resolve
- ProjectChatPage defers getProject refetch to after stream completes to
  prevent mid-stream setProject re-renders that pop tool cards back open

Two bugs caused the tool-use accordion to appear mid-sentence:
1. tool_call_start incorrectly called pushEvent(), which finalized the
   in-flight content block prematurely before the text was complete.
2. finalizeStreamingContent() only checked the last event; after fix 1
   the last event is the tool_call_start placeholder, so the streaming
   content block (second-to-last) was never committed and the drip text
   was lost.

Fix 1: tool_call_start bypasses pushEvent() and appends the placeholder
directly, leaving the content block open.
Fix 2: finalizeStreamingContent() scans backwards through the event array
to find the streaming content block regardless of its position.