v5.9.0 — Honest savings, end to end

Token Optimizer's Savings view now leads with a clear before/after transformation: what your workload would have cost the heavy way versus what it costs now, with every number documented and defensible.

Highlights

• Before/after transformation headline with a plain-language breakdown of where the savings come from.
• New methodology doc (docs/METHODOLOGY.md): the exact source, formula, and conservative assumptions behind every number, written to hold up to a skeptical reader.
• Three honest tiers kept distinct: measured (directly metered), estimated (grounded in your own behavior, with sample sizes), and opportunity (reclaimable, never counted as realized).
• Fair, sample-size-independent baseline math so the before/after comparison holds whether you have a handful of recent sessions or hundreds.
• Readability pass on the Savings panel: collapsible explainers, larger type, clearer copy.
• Cross-session continuity recovery for OpenCode and OpenClaw.