dropthejase stops chat from losing the thread

Chat in dropthejase's fork had a memory problem. The first message in a conversation never saved where it belonged, so the second message couldn't pick up where the first left off - every chat effectively started over after a single turn. dropthejase fixed that, and cleaned up a related issue where the system only recognised chat history saved one particular way and quietly missed sessions recorded through a second path.

Two more fixes round it out. Switching between projects no longer drags the previous project's conversation into the new one, and documents that were never saved with a version no longer crash the whole page when the assistant tries to read them. Together it's the unglamorous reliability work that decides whether people trust a chat tool day to day.