Make keyboard entry and return semantics consistent - #232

The return stack reads well and the c / g T split is a clear improvement — one entry, one frame, one Escape is a much easier rule to hold than the rung ladder. Three things I'd want settled before this lands, all about a frame's active() being wider than the layer it names, plus one now-false comment.

The register-completeness one is the important one: RETURN is spliced into the dispatcher's stack but is not in SCOPES, and createReference walks SCOPES.toReversed(). So ? never names navigation.return, and it still lists navigation.back — whose does reads off rung() — as the page's Escape while the dispatcher is running the frame's. That is the reference and the press spelling one key differently, which the register invariant in skills/leaf/CLAUDE.md and the "three lists" comment above SCOPES both exist to prevent.

One more, outside the diff. version.js's comment block above closeVersionMenu still reads:

so every door into this menu shows it from the button and the way back out is the platform's on all of them: the pointer because the press focuses the button first, v because the row focuses it before running that same press, and the reference because it stands a layer back up from that layer's invoker.

CHOOSER.run is now () => versionBtn.click(), so the middle clause is false and the v door's way back is the return frame rather than the platform's. Worth rewriting alongside the CHOOSER comment this PR already updated.

Nothing to say about the paintAnchors try/catch in 1c49ebb — it reads correct, and resetting anchoringReady before rethrowing is the right half of that pair.