Polish round: node-delete chrome + rename alignment

Owner polish dispatch (2026-09-23):

- Right-click no longer pins a node or opens the detail card: the
  canvas pointerdown/up handlers now gate on the primary button, so
  the context menu arrives alone.
- Node context menu: label is just "Delete" and the shell hugs its
  content (w-44 -> w-fit); the menu body keeps focus for arrow
  cycling but never shows the browser's default focus ring
  (outline-none on the MenuShell body - applies to every menu).
- Delete confirm: "Delete node?" title in CMU Serif, red
  (text-destructive); the node name sits below in JetBrains Mono
  inline-code; the Delete button carries the destructive treatment
  (border + tint, fill deepens on hover). Rest of the dialog stays
  neutral.
- Sidebar rename row: text and metadata stay at the idle row's x -
  the status spacer and the input's border/padding are gone; the
  underline is the only editing cue.

components/graph-canvas.ts

@@ -868,6 +868,11 @@ export class GraphCanvasRenderer {
 	};
 
 	private onPointerDown = (e: PointerEvent) => {
+		// Primary button only (owner, polish round): a right-press must not
+		// pin the node — right-click belongs to the context menu alone, and
+		// the right-pointerup must never read as a click (the detail card
+		// used to open under the menu).
+		if (e.button !== 0) return;
 		const pos = this.eventPos(e);
 		const node = this.pickAt(pos.x, pos.y);
 		if (node && this.sim) {
@@ -898,6 +903,7 @@ export class GraphCanvasRenderer {
 	};
 
 	private onPointerUp = (e: PointerEvent) => {
+		if (e.button !== 0) return; // right-click is context-menu territory
 		// Node press ending: click (no slop) → select; drag → release-and-relax.
 		if (this.dragId) {
 			const id = this.dragId;