dsh provides new Spotlight Session streamlined session view

Key features

• Keyed slots are owned, not shared.
• No Inspect / details-panel deep links.
• The chat's rows render through slots like conversation.chat.node, tool.call.toolview, and conversation.chat.turnTail.
• Those slots are declared by the chat entries themselves, and the slot system rejects a second declaration at load time — the conflict is the design speaking.
• A plugin cannot insert its own rows into the chat transcript, and cannot even declare the chat's own slots.