chore: establish YCode replication baseline and TODO

scripts/import-workbuddy-session.mjs

@@ -0,0 +1,87 @@
+// Import an inert conversation from REA Evidence. Never reads WorkBuddy storage directly.
+import fs from 'node:fs/promises'
+import path from 'node:path'
+import { createHash, randomUUID } from 'node:crypto'
+import { pathToFileURL } from 'node:url'
+import { build } from 'esbuild'
+import { execFileSync } from 'node:child_process'
+
+const args = process.argv.slice(2)
+const evidencePath = args[0]
+const destination = args[1]
+const title = args[2] || '开始新会话'
+if (!evidencePath || !destination || !path.isAbsolute(destination)) {
+  throw new Error('Usage: node scripts/import-workbuddy-session.mjs <REA export> <absolute YCode sessions.json> [title] [--apply]')
+}
+const evidence = JSON.parse((await fs.readFile(evidencePath, 'utf8')).replace(/^\uFEFF/, ''))
+if (evidence.operation !== 'export_selected_conversation_text' || evidence.provider?.id !== 'rea-selected-conversation-text' ||
+    !/^ev_[a-f0-9]{64}$/.test(evidence.evidence_id)) throw new Error('Expected a REA selected transcript Evidence')
+const source = evidence.normalized_result.file
+const sha = data => createHash('sha256').update(data).digest('hex')
+if (sha(Buffer.from(source.text)) !== source.sha256 || Buffer.byteLength(source.text) !== source.bytes) {
+  throw new Error('REA transcript digest/byte count does not match')
+}
+await build({ entryPoints: ['src/shared/workbuddy-import.ts'], bundle: true, platform: 'node', format: 'esm',
+  outfile: '.tmp/workbuddy-import-converter.mjs', logLevel: 'silent' })
+const { convertWorkBuddyJsonl } = await import(pathToFileURL(path.resolve('.tmp/workbuddy-import-converter.mjs')).href)
+const originalBytes = await fs.readFile(destination)
+const existing = JSON.parse(originalBytes.toString('utf8').replace(/^\uFEFF/, ''))
+if (!Array.isArray(existing.sessions)) throw new Error('Invalid YCode session store')
+if (existing.sessions.some(session => session.messages?.some(message => message.status === 'streaming'))) {
+  throw new Error('YCode has unfinished persisted messages; finish the active run before offline import')
+}
+const sourceId = evidence.normalized_result.session_id
+const duplicate = existing.sessions.find(session => session.importProvenance?.sourceSessionId === sourceId)
+if (duplicate) {
+  console.log(JSON.stringify({ status: 'already-imported', sessionId: duplicate.id, title: duplicate.title }))
+  process.exit(0)
+}
+const importedAt = Date.now()
+const result = convertWorkBuddyJsonl(source.text, { sessionId: randomUUID(), title,
+  sourceSessionId: sourceId, evidenceId: evidence.evidence_id, sourceSha256: source.sha256,
+  importedAt, branchMode: 'visible' })
+const exportedImages = new Map((evidence.normalized_result.attachments ?? []).map(image => {
+  const bytes = Buffer.from(image.data_base64, 'base64')
+  if (sha(bytes) !== image.sha256 || image.sha256 !== image.blob_id || bytes.length !== image.bytes ||
+      !['image/png', 'image/jpeg', 'image/webp', 'image/gif'].includes(image.mime)) throw new Error('Invalid REA image artifact')
+  return [image.blob_id, image]
+}))
+let copiedImages = 0
+for (const reference of result.provenance.referencedAttachments ?? []) {
+  const attachment = result.messages.find(message => message.id === reference.messageId)?.attachments?.find(item => item.id === reference.attachmentId)
+  const image = exportedImages.get(reference.sourceBlobId)
+  if (!attachment || !image) throw new Error('A referenced image is unavailable in the REA export; no import performed')
+  attachment.previewUrl = `data:${image.mime};base64,${image.data_base64}`
+  copiedImages++
+}
+if (copiedImages === result.provenance.referencedAttachments.length) {
+  result.warnings = result.warnings.filter(warning => !warning.startsWith('Image attachment references were retained'))
+}
+const session = { ...result.meta, updatedAt: importedAt, messages: result.messages, importProvenance: result.provenance }
+await fs.writeFile('.tmp/workbuddy-copy-session.json', JSON.stringify(session, null, 2))
+const report = { applied: false, title, sessionId: session.id, sourceSessionId: sourceId,
+  evidenceId: evidence.evidence_id, sourceSha256: source.sha256, stats: { ...result.stats, copiedImages }, warnings: result.warnings,
+  existingSessionCount: existing.sessions.length, destination }
+if (args.includes('--apply')) {
+  if (process.platform === 'win32') {
+    const executable = path.resolve('node_modules/electron/dist/electron.exe').replaceAll("'", "''")
+    const processIds = execFileSync('powershell.exe', ['-NoProfile', '-Command',
+      `Get-CimInstance Win32_Process -Filter "Name='electron.exe'" | Where-Object { $_.ExecutablePath -eq '${executable}' -and $_.CommandLine -notmatch '--type=' -and ($_.CommandLine -match '\\s\\.\\s*$' -or $_.CommandLine -match 'out[\\\\/]main') } | Select-Object -ExpandProperty ProcessId`],
+    { encoding: 'utf8', windowsHide: true }).trim()
+    if (processIds) throw new Error('Close the YCode app before applying an offline import so its main-process cache cannot overwrite the copy')
+  }
+  const currentBytes = await fs.readFile(destination)
+  if (sha(currentBytes) !== sha(originalBytes)) throw new Error('YCode store changed during import; no writes performed')
+  const backup = `${destination}.before-workbuddy-${importedAt}.bak`
+  await fs.copyFile(destination, backup, 1)
+  const expected = { ...existing, sessions: [...existing.sessions, session] }
+  const temp = `${destination}.import-${randomUUID()}.tmp`
+  await fs.writeFile(temp, JSON.stringify(expected, null, 2))
+  await fs.rename(temp, destination)
+  const restored = JSON.parse(await fs.readFile(destination, 'utf8'))
+  if (JSON.stringify(restored) !== JSON.stringify(expected)) throw new Error(`Import readback failed; backup: ${backup}`)
+  report.applied = true
+  report.backup = backup
+}
+await fs.writeFile('.tmp/workbuddy-copy-report.json', JSON.stringify(report, null, 2))
+console.log(JSON.stringify(report))