Let a Start input or a variable name the state machine it carries

A sub-behavior that gets its machine through a Start input had no
state ports on Is in state, Set state and the other state nodes.
Their ports came only from an inline pick or a State machine literal,
so a machine handed in from outside left them empty.

- A statemachine port of a Start node can now name a machine
  (DeclaredPort.machine). The inspector shows the pick next to the
  port name. SetPortMachineCommand sets it with undo.
- machineIdOf follows an edge from such a port to that machine, so
  the state nodes it feeds offer its states.
- A Run behavior node has the machine picked in advance on that input.
- A different pick there is allowed, but the node warns, because the
  called graph asks for the states of its own machine.
- A statemachine variable of a Variables node can name a machine
  the same way, picked next to the variable's row.
- The inspector signature of a node now includes the picked machine.
  Before, the pick changed the ports but the dropdown kept its text
  until the node was selected again.
- A local machine handed in still starts in no state every call.
  That rule from #229 is unchanged.

Tests:
- tests/core/start-machine.test.ts (7): ports with and without a
  machine and undo, save and load, the preset value moving a shared
  machine through the call, the warning, a port of another kind,
  the inspector signature, a Variables node.
- Counter checks: without the new branch in machineIdOf 2 tests
  fail, without the machine in the signature 1 test fails.
- Gate on melektaus-atx: 239 files, 3599 tests, CHECK EXIT 0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/editor/inspector/nodeSection.ts

@@ -25,7 +25,7 @@ import {
 } from '../../core/graph';
 import type { GraphAsset } from '../../core/model/Asset';
 import { graphLookup } from '../../core/model/graphLookup';
-import { findGraphAsset, type Project } from '../../core/model/Project';
+import { findAssetOf, findGraphAsset, type Project } from '../../core/model/Project';
 import { type PropertyValue, textOf } from '../../core/model/Properties';
 import {
   isListNode,
@@ -62,7 +62,14 @@ export function nodeSignature(project: Project, assetId: string, nodeId: string)
         .filter((p) => edgesInto(asset.graph, node.id, p.key).length > 0)
         .map((p) => p.key)
     : [];
-  const declared = (node.ports ?? []).map((p) => `${p.key}:${p.kind}${p.write ? ':set' : ''}`).join(',');
+  // The machine a port carries is drawn as the picker's text, its name included.
+  const machineOf = (id: string) => findAssetOf(project, id, 'statemachine')?.name ?? '';
+  const declared = (node.ports ?? [])
+    .map(
+      (p) =>
+        `${p.key}:${p.kind}${p.write ? ':set' : ''}${p.machine ? `:${p.machine}:${machineOf(p.machine)}` : ''}`,
+    )
+    .join(',');
   // They decide which rows the inspector builds, and two behaviors may share a name in the title.
   const target = `${textOf(node.params[OBJECT_TYPE_PARAM] ?? '')}:${textOf(node.params[OBJECT_BEHAVIOR_PARAM] ?? '')}`;
   // The transition rows and the picked name are drawn, not filled in by `refreshNodeSection`, so