fix: highlight same-net schematic traces on hover

[time-turner42]

/claim tscircuit/tscircuit#1130
/fixes tscircuit/tscircuit#1130

Summary

Fixes same-net schematic trace hover highlighting for tscircuit/tscircuit#1130.

• Adds useTraceNetHoverHighlight to map rendered schematic trace DOM nodes back to their source_trace_id.
• Highlights every visible SVG path whose schematic trace shares the hovered trace's source trace/net.
• Restores each path's original stroke on mouseout and keeps highlight active when moving between segments in the same net.
• Wires the hook into SchematicViewer.

Test Plan

• npm_config_userconfig=/dev/null npx tsc --noEmit
• git diff --check

Bounty / issue

Refs tscircuit/tscircuit#1130

Algora board listed this issue as a $25 open bounty at time of work. Please confirm bounty eligibility/claim requirements.

[vercel]

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Project	Deployment	Actions	Updated (UTC)
schematic-viewer	Ready	Preview, Comment	May 10, 2026 3:56am

[time-turner42]

I updated the PR body with the Algora claim commands for tscircuit/tscircuit#1130.

Preview is ready here: https://schematic-viewer-git-fork-time-turner42-fix-tr-3c85cc-tscircuit.vercel.app

Checks are passing and the PR is mergeable. If this satisfies the hover-highlight bounty, could a maintainer please review/merge/reward? I am available for quick changes.