[Bug] Workflow fan-out multiplier not validated against agent-count guideline

Bug Description

▎ - What happened: The Workflow tool description stated "This session has the default workflow size guideline:
▎ medium — keep workflows under 15 agents." The model authored a review workflow with 7 finder lenses, each
▎ finding then verified by 3 refuters spawned per finding, plus a synthesis agent. Worst case that is 7 + (7 × N
▎ findings × 3) + 1 agents, well over 100, with no cap on findings per lens. The model did not count the fan-out
▎ against the stated guideline before launching, and did not warn the user about expected cost.
▎ - What the user said: "seems like la want to burn my tokens your not being efficient with tocken and economic"
▎ - Repro: Session with the medium workflow size guideline active. User types the "ultracode" opt-in keyword with
▎ no other task text. Model selects a review target and authors a per-finding fan-out verify stage without
▎ bounding the finding count.
▎ - Evidence: Run ID wf_1ab98362-deb; workflow stopped by the model via TaskStop after the user objected. Session
▎ on 2026-09-03. Guideline text appears verbatim in the Workflow tool description.
▎ - Cause: Per-finding fan-out multiplies with an unbounded intermediate result; the agent-count guideline is
▎ expressed as a flat number, which is easy to check against a static agent list but not against a multiplicative
▎ pipeline. A cap on findings per lens, or a single verifier instead of three, would have kept it in budget.

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.258
• Feedback ID: 2ba5afe3-3df8-4504-9b05-44861b0f9d3b

Errors

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