README and business plan: one engine, three answers, v2 measured cost

README adds the three commands with their real results: bisect proved the dbt guide never worked in a clean environment, and prerequisite proofs passed on AccuKnox, MkDocs and Entire. The business plan replaces the assumed recovery multiplier with v2 measured cost, 0.02232 USD per run, Team margin 86.3 percent and Scale 77.6 percent, and prices bisect probes at compute only.