VoiceOS ignores MCP server instructions; put routing rules in tool descriptions

VoiceOS 0.1.40 never reads the MCP initialize instructions field, so guidance placed there reaches no model. Only tool descriptions and input schemas do, and VoiceOS doesn't truncate them on the Mac side. Each agent turn also gets only the last 5 turns as plain text (user words plus spoken reply), with no tool calls or results, so ids returned by an earlier tool are lost across turns. Put conversation rules (draft vs post wording, 'latest instruction wins', reuse the same item) in the write tools' descriptions. Have the agent speak one line naming the item when it shows a confirmation card, so the name survives in the text history. For durable context, a manifest transcript hook (hidden voiceos_hook_transcript tool) can return additionalContext of up to 4,000 chars per turn.