Land pi-mono borrow B1 — requestedModel/responseId provider-audit fields (only spec in main; held in local stash)

[omerakben]

Accepted-but-unlanded pi-mono borrow B1 (requestedModel? / responseId? provider-audit fields), currently held in a local git stash (stash@{1}) — not on any branch or remote.

What it is: +291 lines across 15 files threading requestedModel? and responseId? through ProviderResponse and the agent_completed event:

• src/providers/{types,claude,codex,xai,fake,fake-script,invoke}.ts
• src/state/{events,schemas}.ts
• docs/references/provider-contract.md
• 5 test files

Status: main's docs/comparison/08-pi-mono/SYNTHESIS.md records B1 as "accepted with naming fix" with a locked spec — but only the spec landed; the implementation lives solely in this stash (verified absent from main by the 2026-05-29 cleanup audit: git grep responseId origin/main -- src/ returns nothing).

To land it later:

• The stash base (feat/pi-mono-borrows @ 94fafd7) is NOT an ancestor of main, so a fresh rebase against the current types.ts / schemas.ts / invoke.ts surfaces is required.

Caveat: this code lives only in a local stash on the maintainer's machine and is fragile. Consider git stash branch <name> stash@{1} to a durable branch if it will not be landed soon.

[omerakben]

Backed up to durable branch feat/issue-43-pi-mono-b1-audit-fields (commit 35fc091), pushed to origin during the 2026-05-29 cleanup. The local stash was consumed in the conversion — this branch is now the single source of truth. Content unchanged: 15 files, +291/-12, on base 94fafd7 (not an ancestor of main, so landing needs a fresh rebase as noted in the issue body).