docs: kithara-dsp spectrum, downmix and sum of squares; kithara-waveform page; analysis on kithara-dsp
docs(dsp): kithara-dsp layout and sanitize kernels, firewheel facade
docs(ui): split kithara-ui into shaping, draw, lottie, input, capture contracts
docs(ring): add kithara-ring contract; pooled rings in bufpool
docs: align bounded scalar contracts with PR 341
docs: publish crate contracts and ownership in the wiki