World tree

[disconcision]

Introduces rooms. Rooms have runes

• Makes the stage branch into a list of stages
• Double-clicking the selected node toggles fold
• Context-clicking an non folded node toggles marks (enfolds) a node
• Context-clicking on an ancestor of an enfolded node toggles fold
• Context-clicking a folded node (un)toggles fold

TODO:

• quasifold / unfold
• default quasifold on stage
• mitigate responsive line threshold issue
• digits: mark (enfold) doesn't show up on digits
• digits: terminal digit atom has weird padding
• digits: alignment off, borders off, backgrounds off
• digits: largest digit doesnt glow (as it is not classed as digit; debatable)
• digits: patterns are slightly borked
• digits: font size mod (1.3em) is messing with the responsive resizing
• TreeTop: Not all non-initial children are going in assigned row
• TreeTop: Marks need to be on top, not on left
• TreeTop: Half-selection outline needs to be on top, not on left
• Infix: restore
• make rooms use lefttree (ish?) formatting even in other projections
• Sound: restore
• add/mult identity has no /visible/ effect at folded root
• atoms in masks get un-tinted during transformation transitions
• node background rises above contents during transformation transitions
• Syntax: Add classes BinOp, UnOp, Atom, Digit-like, Room-like
• Syntax: Convert BinOps styling new syntax model