shape at cursor. e.g. b x | x remove at cell / at cursor. oops bring back the last project rendered obsolete. oops-my-bad arm the anchor: tap one stone, every stone connected to it is offered — `swap
` restyles the caps,
                                 `cut` removes, `keep` releases.
     save  / saves         name the selection — it becomes a word. `saves`
                                 lists your library; punch a name to build it anywhere.
     newmap                      a fresh field. old saves travel with you;
                                 `oops` brings the old field back.
     send  / take     send your build to your friends — the code
                                 IS the build. they `take` it, it joins their library.
     did                         no audio — just "this is what you did": 1. 2. 3.,
                                 the progress, staying visible. tap a row, tap an
                                 anchor stone — the code runs right there.
     lock / unlock / anchors      lock in to new anchor points — tap stones, gold
                                 rings mark them; `anchors` counts them.
     portal  / unportal       an anchor of a block as a portal to a build site —
                                 tap the block, tap it again and you meet me there.
   Repeat:     3(b2r)            run the inner line N times.
   Procedure:  tower, wall...    (MARK: PROCEDURES)
   Flip:       flip        mirrored expansion. (MARK: MIRROR)
   Multi:      split on ';'.     e.g. l 8 10 10; c 4 0 10
   Stamps: procedures build AT the cursor but leave it where it stood —
           atoms move the cursor, procedures do not. castle; castle steps over.
   EDIT: token shapes, new verbs, new directions.
   ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ */
var DIRS = {r:[1,0], l:[-1,0], u:[0,-1], d:[0,1]};   /* 1 block = 1 grid cell = 2 units */
var BLOCK = 2;

function parseLine(line, ec){
  var ops = [], parts = String(line).split(';');
  for(var pi=0; pi=1 && n<=HARDEN.MAX_REPEAT)) return {ok:false, error:'repeat out of range'};
    if(depth+1 > HARDEN.MAX_DEPTH) return {ok:false, error:'too deep'};
    var ops = [];
    for(var i=0;i