Human pass over the main README

The README was rewritten in one pass (3f6fbb3) to lead with ownership rather than with the framework internals. The structure and the claims are, I think, right. The wording has not been read by anyone yet. It needs eyes from the two audiences it is actually aimed at, because they will trip on different things. **Someone who would adopt this.** Ad-tech side, evaluating whether to stop renting a platform. Does the first screen answer "why would I do this" before it explains what the software is? Is "one developer is enough to run it" believable as written, or does it read as a sales line? Is the white-label contrast fair, or overstated to the point where a reader stops trusting the rest? **A developer who would work in it.** Is "For developers" enough to start, or does it skip a step? The fail-open paragraph is the one I most want checked — it is the part where the old text was actively wrong, and being merely less wrong is not the goal. Specific things worth challenging: - Whether the trust paragraph earns its place or reads as posturing. One line was the deliberate limit; it may still be one line too many. - Whether "Own your RTB stack" is the right opening or a slogan. - Anywhere the English is stiff, over-hedged, or sounds translated. - Anything stated as fact that should be verified before a stranger relies on it. Rewrite freely rather than annotating. It is easier to argue with a version than with a comment.