Reviewer caught that the new `legacy-pi-ai-shim.ts` is only referenced
via a computed string path, so Bun's `--compile` static analyzer cannot
trace it into bunfs. The same gap existed for the pre-existing
`typebox.ts` shim — `path.resolve(import.meta.dir, "../typebox.ts")`
collapses to `/$bunfs/typebox.ts` in compiled mode (where
`import.meta.dir` is `/$bunfs/root`), which does not exist in bunfs.
Legacy plugins importing bare `@sinclair/typebox` or `@(scope)/pi-ai`
therefore hit "Cannot find module" in release builds.
- Branch `TYPEBOX_SHIM_PATH` and `LEGACY_PI_AI_SHIM_PATH` on
`isCompiledBinary()`: in compiled mode they point at the
`--root`-relative bunfs entry path with a `.js` extension
(`/$bunfs/root/packages/coding-agent/src/extensibility/<file>.js`);
in dev they keep the `path.resolve(import.meta.dir, "../<file>.ts")`
source path so tests still resolve against the workspace tree.
- List both shims as additional `--compile` entrypoints in
`scripts/build-binary.ts` so Bun actually emits them into bunfs at the
paths the runtime expects.
Verified with a focused `bun build --compile` probe: `Bun.resolveSync`
returns the expected bunfs path for both shims when they are listed as
entries, and fails when they are not. Dev-mode test suite unchanged
(17 pass / 0 fail across the four legacy-pi compat test files).