Replaces the Mosaic 0.18 string-frame renderer with tamboui 0.2.1-SNAPSHOT
to unlock a cell buffer, widget catalog, and real layout engine. Domain
core (state/reducer/ws/input) is unchanged; only the renderer and the key
mapper are rewritten. Fixes a latent Mosaic-mapper bug where q/n/c/a/r/s//
were swallowed inside input modes by making the new mapper mode-aware.
