[Bug] Agent teammate display uses agentType instead of assigned name in fleet view

Bug Description
Title: Agent-team teammates display by agentType, not their assigned name (fleet view + on re-entry)

Version: 2.1.234 · macOS · iTerm2, teammateMode auto (native panes working)

Summary: When spawning named teammates, the assigned name only appears transiently in the pane's bottom-right corner at spawn. The persistent display identity — the fleet/agents list and the pane label on re-entry — uses the teammate's agentType instead of its name.

Repro:

1. Spawn two teammates with subagent_type: "claude", distinct names (greeter-one, greeter-two). → Both render as "claude" in the fleet list; re-entry relabels panes to "claude".
2. Spawn two with distinct types (general-purpose, Explore), names alpha/beta. → Fleet list shows general-purpose / Explore; re-entry relabels panes to the type.

Impact: Same-type teammates are visually indistinguishable in the fleet view regardless of the names assigned — you can't tell them apart at a glance. The name is stored in ~/.claude/teams/<session>/config.json and still works for messaging/addressing; it's just not the display key.

Expected: Fleet list and re-entry label should show the assigned teammate name (or name (agentType)), matching the pane corner.

Docs gap: The name-vs-type display contract isn't documented in agent-teams.md.

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.234
• Feedback ID: 6469b50e-7f6c-461f-b2d2-cd03f0368e16

Errors

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