feat: rebrand QuestboardAI -> TaskFlow everywhere (UI, locales, index.html)

feat: implement chat memory, remove backdrop blur, autoscroll on open, and multiple chat threads per project

gemini integration

feat: rebrand PlotTwist to QuestboardAI

feat: rebrand TaskFlow to PlotTwist and align with Human-in-the-Loop AI Agent Proof-of-Work vision

init