Adds the max context size to switch.sh --list. registry-emit threads a ctx label through the variant TSV (before status_note); switch.sh renders it rightmost. Production -> bare ctx; caveats/NA -> folded into the health paren (comma-separated). Rounded to nearest K (163840->164K; 32768 reads 33K). Shows registry vs compose default as a single value when they match, 'validated/compose' (e.g. 164K/200K) when they drift -- the only 3 drifts are experimental lanes; all production/caveats match. Suite 38/38.