[BUG] Web UI hides bash output during execution despite streaming data being available #22116

Description

Tthe web UI hides tool output until the command completes. The streaming pipeline already delivers output chunks to the client -- props.metadata.output updates reactively during execution. However, three UI gates prevent it from being visible:

1. BasicTool's handleOpenChange blocks toggling the collapsible during both pending and running states
2. BasicTool's Collapsible.Arrow is hidden during both pending and running states
3. The bash tool's description subtitle is hidden during both pending and running states

Additionally, the collapsible starts closed by default and there's no mechanism to auto-open it when a command starts executing.

Plugins

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OpenCode version

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Steps to reproduce

!for i in 1 2 3 4 5; do echo $i; sleep 1; done

Screenshot and/or share link

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Operating System

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Terminal

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