runtime: createRequire rejects node:-prefixed builtins / missing diagnostics_channel — pi wall #3 (require('node:diagnostics_channel') via bundle shim) #6644

Wall #3 of the pi coding-agent bring-up (tracker #6564; walls #1 #6593 and #2 #6604 fixed). With both fixes applied, the compiled pi binary gets through module init and dies at:

Error: Perry createRequire() currently supports built-in modules only; package/file require('node:diagnostics_channel') is not supported

Site: lru-cache's node build (pi bundle line ~5520) does require('node:diagnostics_channel') through the bundle's createRequire(import.meta.url) shim (the esbuild createRequire banner pattern — any ESM bundle of CJS deps produces this shape).

So perry's createRequire either (a) doesn't include diagnostics_channel in its builtin set, or (b) rejects the node:-prefixed form on this path while supporting the bare name. Both are worth fixing:

• normalize node:-prefixed specifiers in createRequire before the builtin lookup (Node accepts both forms);
• ensure diagnostics_channel is present as at least a functional stub (channel(), hasSubscribers, subscribe/unsubscribe, tracingChannel) — lru-cache only uses it for optional diagnostics, so a spec-shaped no-op channel suffices for this consumer, though a real implementation serves opentelemetry-adjacent code later.

Repro: HOME=$(mktemp -d) /Users/amlug/projects/perry/secret-tests/pi-target/dist/pi-native --help (binary built from the #6603+#6604 branches), or reduce to: an ESM file with const require = createRequire(import.meta.url); const dc = require('node:diagnostics_channel'); console.log(typeof dc.channel).