Fix pushbutton externally connected pins

[rushabhcodes]

Summary

Fix externallyConnectedPins support for <pushbutton /> components.

PushButton now creates the requested source-level traces, matching the behavior already implemented by Chip. A regression test verifies that SW1.pin1 connects to SW1.pin2 in the generated circuit JSON.

Validation

• Focused pushbutton tests pass
• bunx tsc --noEmit passes
• Formatting and diff checks pass

Issue

Fixes #3118

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Project	Deployment	Actions	Updated (UTC)
tscircuit-core-benchmarks	Ready	Preview	Aug 12, 2026 3:54pm

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[imrishabh18]

I am confused, can you explain more about the issue?

[rushabhcodes]

@imrishabh18
The issue is that <pushbutton /> accepts the externallyConnectedPins prop, but currently ignores it during rendering.

For example:

<pushbutton
  name="SW1"
  externallyConnectedPins={[["pin1", "pin2"]]}
/>

This should create a source_trace connecting SW1.pin1 and SW1.pin2, similar to how <chip /> handles the same prop. Before this PR, no source_trace was created even though the prop passed TypeScript/Zod validation.

This PR adds that missing trace creation behavior and includes a regression test for it.

[seveibar]

@rushabhcodes pushbuttons don't usually have externallyConnectedPins

[seveibar]

i'm sort of confused why you want this

[seveibar]

i don't think this is based on a real issue, we shouldn't spend our time on stuff that isn't actually used