Fix Prompt Builder Nitro build by inlining sequence helpers in utils.

The relative re-export of shared/prompt-sequences.mjs left an unresolved import in the SSR bundle.

tests/prompt-sequences.test.mjs

@@ -1,12 +1,28 @@
 import test from 'node:test'
 import assert from 'node:assert/strict'
-import {
+import { readFileSync, writeFileSync, unlinkSync } from 'node:fs'
+import { join } from 'node:path'
+import { tmpdir } from 'node:os'
+import { pathToFileURL } from 'node:url'
+import ts from 'typescript'
+
+const src = readFileSync(new URL('../utils/promptSequences.ts', import.meta.url), 'utf8')
+const js = ts.transpileModule(src, {
+  compilerOptions: {
+    target: ts.ScriptTarget.ES2022,
+    module: ts.ModuleKind.ESNext
+  }
+}).outputText
+const tmp = join(tmpdir(), `prompt-sequences-${process.pid}.mjs`)
+writeFileSync(tmp, js)
+const {
   assembleSceneText,
   assembleSequenceText,
   formatCharacterLine,
   emptyScene,
   cloneSceneForNext
-} from '../shared/prompt-sequences.mjs'
+} = await import(pathToFileURL(tmp).href)
+unlinkSync(tmp)
 
 test('formatCharacterLine covers name/description cases', () => {
   assert.equal(formatCharacterLine({ name: 'Ada', description: 'tall' }), 'Ada: tall')