feat(backlog): add the per-task JSONL metrics record

One record per task at outcome time, appended to the project's .ai/metrics/work-the-backlog.jsonl. The field table follows the spec, with commit_sha called out as the corrections-signal key and comma-separated when a task decomposes into several commits. A failed append warns in the run summary but never blocks or aborts the run.

I added the "failed" outcome the spec's error-handling section required but its enum missed: a mid-implementation failure leaves the tree working, gets surfaced, and the run continues.

1 files changed, 2 insertions, 2 deletions

diff --git a/todo.org b/todo.org
index eadd5d9..5135bc1 100644
--- a/todo.org
+++ b/todo.org
@@ -471,8 +471,8 @@ Pinned the waiver format per D5: two marker lines in .ai/notes.org Workflow Stat
 *** 2026-07-02 Thu @ 01:21:47 -0400 Phase 4 landed — checklist mechanics, pre-flight Q&A contract, page
 The four-item checklist (in since Phase 1) gained its mechanics: a VERIFY-filing subsection (dedup against an existing sibling first — the deferred task stays TODO, so without the check every run re-files; placement/heading/body per todo-format.md) and a quick-question routing subsection (discriminator: one-line factual/preference pick vs tradeoff-weighing; three-plus questions = underspecified = file; item 2 data-loss never routes to Q&A). Preset section gained the batch-ask contract (one message, recommendation-first numbered options per interaction.md, answers recorded as dated lines in the task bodies before the run). Page section finalized (fires once on set-done or cap-hit; notify --persist is the paging surface). Common Mistakes 12-13 added. Checklist only ever reduces what runs; pre-flight fires only under the preset.
 
-*** TODO [#C] Phase 5 — per-task JSONL metrics log :feature:solo:
-Append the per-task record to .ai/metrics/work-the-backlog.jsonl at each task outcome. Spec Phase 5. Verify: logging never alters execution.
+*** 2026-07-02 Thu @ 01:24:50 -0400 Phase 5 landed — per-task JSONL metrics log
+Metrics section written into work-the-backlog.org: one record per task at outcome time, appended to the project's .ai/metrics/work-the-backlog.jsonl (git-tracked, append-only, dir+file created on first append). Full field table per the spec (ts, run_id, project, caller, task, outcome, defer_reason, upfront_decision, wall_clock_s, commit_sha, review_findings), outcome slugs mapped to the prose vocabulary, commit_sha flagged as the corrections-signal key (comma-separated when a task decomposed into several commits). Added the sixth outcome the spec's readiness section demanded but the enum missed: failed (tree left working, surfaced, run continues) — wired into the Outcomes vocabulary and loop step 4. A failed append warns in the run summary but never blocks, reorders, or aborts execution.
 
 *** TODO [#C] Phase 6 — synthesis to org-roam :feature:
 Read the JSONL union, compute per-run + trend metrics, write a KB node under ~/org/roam/agents/ per knowledge-base.md (personal-projects-only classification enforced). Spec Phase 6. Verify: read-only over the logs plus one KB write.