Show callers and callees and highlight the active function on the maps

[valuecodes]

What

• Part 2/5 of Post-MVP additions: stats and unloading, ambiguous chooser, recursion breadcrumb, callers/callees: who calls the current function and whom it calls, plus the active function on both maps.
• New @repo/code-graph/call-index: callIndexOf(graph) (memoised per graph) gives callers and callees from the call edges, flagging recursion, and groups each ambiguous call's candidates.
• The source panel (E) adds called by … and calls … · maybe Circle.render() | Square.render() lines. Each list is cut at 5 names plus +n, ↻ marks self-calls, and the file is added when shown names collide.
• The local map outlines the rooms of the function you're in more brightly. The Tab map draws them in a separate highlight layer that stays visible zoomed out and keeps the memoised layers from re-rendering. It uses no inline <style>, which the production CSP (style-src 'self') would block.

How to test

pnpm test
pnpm typecheck
pnpm --filter web dev   # open /?code=resolution, walk into main(), press E; press Tab

Security review

No security-impacting changes.

🤖 Generated with Claude Code

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Reviewed commit: 3ee61c60a2

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-13T19:02:53.154029Z	3ee61c6	PR opened

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