Trim needless comments and fix the picker width

Remove comments that only restate the code, keeping the section banners
and the notes that carry a reason, a measured fact or an external
contract.

ButtonOptions.width claimed to be a fixed width but only set minWidth,
so the Graph and Texture pickers grew with the name they showed. It is
now what it promises, with a separate minWidth for the buttons that have
two forms. Narrow buttons shrink their padding, otherwise a 24px icon
button had 8px left for its glyph and truncate dropped it entirely.

__gm.labelsDropped() guards that class: the overflow guard only saw text
that was too wide, never a label truncated to nothing.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/core/graph/nodes/shared.ts

@@ -12,7 +12,6 @@ export const str = (key: string, label = key): PortDef => ({ key, label, type: '
 export const obj = (key: string, label = key): PortDef => ({ key, label, type: 'object' });
 export const any = (key: string, label = key): PortDef => ({ key, label, type: 'any' });
 
-/** The same port with an inline value it carries while unconnected. */
 export const withDefault = (port: PortDef, value: PropertyValue): PortDef => ({ ...port, default: value });
 
 /** Outputs of the three collision events: the other body, its collider and the own collider. */
@@ -36,15 +35,11 @@ export const variableParam: PropertyDef = {
   options: [],
 };
 
-/**
- * A reference to an asset the node acts on (spawns, compares against). No `assetTypes`: any
- * placeable asset is a valid answer, and restricting them would be guessing for the user.
- */
+/** No `assetTypes`: any placeable asset is a valid answer here. */
 export const assetParam: PropertyDef = { key: 'asset', label: 'Asset', kind: 'asset', default: '' };
 
 // --- node factories --------------------------------------------------------------------------
 
-/** A data node computing one number from `a` and `b`. */
 export function binaryMath(type: string, description: string, fn: (a: number, b: number) => number): NodeDef {
   return {
     type,
@@ -58,7 +53,6 @@ export function binaryMath(type: string, description: string, fn: (a: number, b:
   };
 }
 
-/** A data node computing one number from `value`. */
 export function unaryMath(type: string, description: string, fn: (value: number) => number): NodeDef {
   return {
     type,
@@ -72,7 +66,6 @@ export function unaryMath(type: string, description: string, fn: (value: number)
   };
 }
 
-/** A data node combining the booleans `a` and `b`. */
 export function binaryLogic(
   type: string,
   description: string,