Summary

The pi-embedded execution engine was gutted in #75, but a transitional stub barrel src/agents/pi-embedded.ts was left behind with no-op implementations so existing callers would compile without import-path changes. This stub and its consumer files need to be cleaned up — every function in the barrel returns a constant (false, 0, "default", empty object) and does nothing.

What to Delete

src/agents/pi-embedded.ts — the stub barrel itself. Contains:

• 4 stub types: EmbeddedPiAgentMeta, EmbeddedPiRunMeta, EmbeddedPiRunResult, EmbeddedPiCompactResult
• 9 stub functions: isEmbeddedPiRunActive (→false), isEmbeddedPiRunStreaming (→false), abortEmbeddedPiRun (→false), waitForEmbeddedPiRunEnd (→true), queueEmbeddedPiMessage (→false), resolveEmbeddedSessionLane (→"default"), getActiveEmbeddedRunCount (→0), runEmbeddedPiAgent (→empty result), compactEmbeddedPiSession (→failure result)

Call Sites to Clean Up

Category A: Remove function call + import (7 production files)

These call abortEmbeddedPiRun() which always returns false — pure no-op, return value unused or irrelevant:

Category B: Replace function call with literal (3 production files)

Category C: Clean up test harnesses (legacy pi-embedded mock naming)

These test files mock ChannelBridge but use legacy piEmbeddedMock variable naming and legacy type shims. They need renaming and cleanup:

Category D: Update other test files with pi-embedded mocks

Category E: Clean extension API

Approach

1. Remove all production imports and calls (Categories A + B) — ~10 files
2. Clean up test harnesses: rename legacy pi-embedded mock naming to ChannelBridge-oriented naming, remove unused mock functions, replace legacy type shims with middleware types (Category C) — 2 files
3. Remove test mocks that reference pi-embedded (Category D) — ~5 files
4. Clean extensionAPI.ts (Category E) — 1 file
5. Delete src/agents/pi-embedded.ts — the stub barrel itself
6. Verify: grep -r "pi-embedded" src/ --include="*.ts" returns zero results
7. Verify: pnpm build passes
8. Verify: pnpm test passes (remaining tests)

Scope

~17 files modified + 1 file deleted. ~80-100 lines changed total.

Context

This is the final cleanup after #75 (gut pi-embedded execution engine core). The stub barrel was a transitional measure to keep the build passing while the engine was removed. With the engine gone, these no-op stubs serve no purpose and should be removed to eliminate dead code references. The test harnesses that mock ChannelBridge using legacy pi-embedded naming should be modernized to use ChannelBridge-native types and naming.