perf(extension): load the compiled entrypoint directly

[gurronen]

Summary

• avoid transpiling the workflow extension's TypeScript graph during every Pi startup

Changes

• compile the Pi extension entrypoint with the existing TypeScript build
• point pi.extensions at dist/pi-extension.js
• replace the extension's package-barrel import with direct module imports
• verify the compiled entrypoint is included in the npm package and exports an extension factory

Testing

• npm test
• npm pack --dry-run --json
• manual pi -e .
• startup benchmark before/after

Startup benchmark

Measured in a fresh Bubblewrap sandbox per run, with networking disabled, an empty temporary home/cache, all normal Pi extension/skill/theme/context loading disabled, and only this extension explicitly enabled. One warm-up was discarded and 10 alternating runs were recorded.

Case	Entrypoint	Median	Range
Without PR (4aaf451)	extensions/workflow.ts	1.941s	1.505–2.245s
With PR (f3a3de9)	dist/pi-extension.js	0.949s	0.784–1.094s
Pi control, no extension	—	0.234s	0.220–0.261s

The compiled entrypoint reduced median total startup by 0.991s (51.1%), or 2.04×. Relative to the no-extension control, median extension overhead fell from approximately 1.707s to 0.715s (58.1%).