Consolidate duplicated editor code, trim comments, refresh README

Split GraphCanvas (1076 -> 831 lines) into EdgeLayer and graphMenus;
the port and marker menus were the same list and are now one function.
Value specs of the inspector and the list tab share valueSpecs.ts, and
the remaining copies (compound commands, type glyphs, typed asset
lookup, name rule, play/editor world setup, marquee) are merged.

Four copies had already drifted apart; merging them fixes:
- "Disconnect N links" in the port menu is one undo step, not N
- "+ Add collider" is hidden on a placed container instance, as in
  the hierarchy menu, instead of always failing
- a bool property coerced from the text "false" becomes false
- a port command on an unknown node type reports instead of crashing

Comment-only edits leave the bundle byte-identical. README corrected in
35 places (step limit, jump-run clock, suite duration, 409 body, ...).

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

tools/e2e/lib/scaffold.mjs

@@ -1,8 +1,6 @@
 /**
- * Steps 17–20 each need the same throwaway rig in the fixture scene: a behavior asset cloned off
- * `mover` carrying the step's own graph, a crate to hold it, and a logic child that runs it.
- * Spelled out per step it drifted four ways – `push` vs `unshift`, three different `make`
- * signatures, and y-offsets nothing kept apart.
+ * The throwaway rig steps 17–20 share in the fixture scene: a behavior asset cloned off `mover` with the
+ * step's graph, a crate to hold it, and a logic child that runs it.
  */
 
 /**
@@ -38,11 +36,8 @@ export const MAKE_OBJECT = `
     };`;
 
 /**
- * Builds the rig and hands back the ids it created, plus `remove()` which takes them out again
- * and returns what is left – so a step's cleanup cannot fall out of step with what it made.
- *
- * `front` puts the asset at the head of the project list: the asset panel is long by this point
- * in the suite, and a row appended at the end scrolls out of reach of `dragAsset`.
+ * Returns the created ids plus `remove()`, so a step's cleanup matches what it made. `front` puts the
+ * asset at the head of the list: a row appended at the end scrolls out of `dragAsset`'s reach.
  */
 export async function scaffoldBehavior(t, options) {
   const {