[WIP] Restore fleet-wide token_usage collection after 6 days of gap

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

---

This section details on the original issue you should resolve

<issue_title>[deep-report] Restore fleet-wide token_usage collection (TokenUsage=0 for ~6 consecutive days)</issue_title>
<issue_description>### Description
The token_usage artifact has been empty fleet-wide (TokenUsage=0) for roughly 6 consecutive days (token data in the 30d chart ends at 06-20). Per-run token efficiency is no longer trackable; cost visibility now relies solely on AI-credits (AIC), and copilot/codex engines report no token counts at all. The Agentic Workflow Audit explicitly flags this as an observability gap that should be fixed.

Investigation / Fix

Determine why the token_usage artifact is empty across engines (claude/copilot/codex/pi). Likely candidates: a regression in the per-engine log parser that emits TokenUsage (see pkg/workflow/claude_logs.go, codex_logs.go, antigravity_logs.go), an artifact-naming/path change, or upstream engines no longer surfacing usage in logs. Restore population of the artifact, or document which engines structurally cannot report tokens so dashboards stop flatlining.

Expected Impact

Restores per-run token-efficiency monitoring across the fleet, re-enabling cost-regression detection that is currently blind. Multiple daily audit agents depend on this signal.

Suggested Agent

Token Audit agent or a Go-capable maintenance agent.

Estimated Effort

Medium (1-4 hours) — investigation across engine log parsers.

Data Source

DeepReport 2026-06-26; Agentic Workflow Audit #41549 (Token Usage 30d chart flatlined since 06-20).

Generated by 🔬 DeepReport - Intelligence Gathering Agent · 255.2 AIC · ⌖ 18.5 AIC · ⊞ 9.8K · ◷

• expires on Jun 28, 2026, 7:35 AM UTC-08:00

• Closes [deep-report] Restore fleet-wide token_usage collection (TokenUsage=0 for ~6 consecutive days) #41734

Comments on the Issue (you are @copilot in this section)

[github-actions]

🤖 PR Triage

Category	chore
Risk	🟢 Low
Priority	Low (score 27/100)
Action	❌ close

Score breakdown: Impact 20 · Urgency 5 · Quality 2

WIP placeholder with 0 changes. Superseded by #41823 (copilot/deep-report-restore-token-usage-again branch — newer active attempt for the same token_usage observability issue). Recommend closing this older abandoned branch to reduce clutter.

Generated by 🔧 PR Triage Agent · 87.6 AIC · ⌖ 14.9 AIC · ⊞ 5.4K · ◷