Fix: High CPU / memory leak when filtering model list window to empty results

[d3vr]

Resolves #6433

When filtering the model selection list in the TUI to a point where no results match (resulting in an empty list), the application enters a CPU and memory spiral, causing 100% CPU usage and rapid memory consumption until the process crashes.

The Fix
Implemented a conditional rendering guard in packages/opencode/src/cli/cmd/tui/ui/dialog-select.tsx.

• Change: Wrapped the <scrollbox> component in a <Show when={grouped().length > 0}> block.
• Result: When the result list is empty, the ScrollBox component is completely unmounted from the render tree. This prevents the upstream ScrollBoxRenderable from ever encountering the hazardous 0-height state, effectively bypassing the infinite loop.

Verification

• Confirmed that typing a filter that yields no results now displays "No results found" without spiking CPU/memory or crashing.
• Confirmed that clearing the filter restores the list correctly.

[d3vr]

Root Cause Analysis
The issue originates in the upstream @opentui/core library's ScrollBoxRenderable component:

1. When the filtered list is empty, our DialogSelect component passes a height of 0 to the ScrollBox.
2. Inside @opentui/core, the ScrollBoxRenderable listens to onSizeChange events to recalculate scrollbar properties.
3. The recalculateBarProps method contains a workaround that unconditionally schedules a re-render on the next tick: process.nextTick(() => this.requestRender()).
4. With a height of 0, the layout engine repeatedly fires onSizeChange (or oscillates), triggering an infinite recursive loop of Layout -> Size Change -> Schedule Render -> Layout.

(DISCLAIMER: I'm not sure this is actually the cause, I'm not too familiar with the opentui codebase, this is Gemini 3 Pro's analysis)

[coleleavitt]

I can one up this I was getting scenarios of using 70GBs of ram but it might be a unrelated memory leak, would it even be feasible for developers to write opencode in Rust?

[rekram1-node]

/review

[github-actions]

lgtm