ox-pr-header

Emit and paste the SageOx credit line at the TOP of a pull-request description — the human-facing counterpart to the machine SageOx-Session: trailer. Run ox pr header at PR-creation time; it renders a thin, on-brand, dark/light-aware line linking the session(s) and plan(s) that produced the change, naming the team, and whispering a subtle enrichment stat. The CLI owns the sanitizer-fragile markup — you never…