Desktop app session list can't adopt existing local CLI sessions — sidebar left empty after Max→Teams account migration

What happened

Migrated a personal Max account to a Teams org (same email, official migration flow). All Claude Code transcripts remained intact on disk under ~/.claude/projects/ (78 sessions, ~78 MB), and the terminal CLI's --resume picker lists and resumes every one of them under the new login. But the desktop app's sidebar shows none of them, and /resume inside a desktop-app chat shows no chats — the app's session registry appears to be account/org-scoped and separate from on-disk history, with no import path.

What I tried

• Resuming sessions from the bundled CLI, both interactively and headlessly (claude -p --resume <id>): the transcripts continue fine on disk, but the sessions never appear in the desktop app.
• The desktop app's own /resume picker in a fresh chat: empty ("no chats"), while the terminal picker in the same folder lists 32.
• The ccd_session_mgmt channel rejects the on-disk session IDs with "Session not found".

The docs confirm the behavior: sessions.md says the desktop app, web, and VS Code extension "each maintain their own session history" — but there's no documented way to bridge them, and the account-migration docs don't warn about this.

Expected

Either of:

1. The desktop app offers to adopt/display local CLI sessions for a trusted project folder (they're already in the standard ~/.claude/projects/ location the app itself writes to), or
2. The account-migration flow warns that the app's session list won't carry over.

Right now the reassurance "your history is local, nothing is lost" is technically true but misleading when the app UI is the primary way a user browses that history — the data survives the migration, the ability to see it in the app does not.

Environment

• Windows 11 Pro (10.0.26200)
• Desktop app bundling Claude Code 2.1.246
• Trigger: personal Max → Teams org migration (same email)

Related

Same symptom (sidebar empty, disk data intact) with different triggers: #83730 (forced reinstall), #87710 (fresh install), #89544 (reinstall), #87423 (app restart), #86277 (data reset). This report adds the account-migration trigger and the feature ask: a supported way for the app to adopt existing local transcripts.