tip leaf: default omitted model tools capability (#50702)

[kvnloo]

Goal

Fork-only tip leaf for origin anomalyco#50702 — default omitted model tools capability to false.

Context

Origin tip SHA 21728771f202689abdb98c0f8942913ce9654a48. Base: fork dev. github_writes_origin=0. Codex promote parked.

Acceptance

• CLEAN fail→pass on tip test defaults configured model tool capability to false when omitted
• GREEN 1 / NEG 1 fail / RESTORE 1

Return

Ship fork PR with grok bot + envelope; no origin writes.