[Bug] Local sessions fail to load in Claude Code tab with "Not found" assets-proxy error

Bug Description
In the Claude desktop app, the Code tab never loads any *local* session.
Every locally-created chat shows permanent skeleton loaders and the composer
refuses to send. A *cloud* session in the same sidebar opens and works fine.

Steps to reproduce
1. Have local Claude Code sessions in ~/.claude/projects/
2. Open the desktop app → Code tab
3. Click any locally-created chat
4. Skeleton loaders stay indefinitely; sending a message does nothing

Expected: the transcript renders from the local .jsonl file.
Actual: skeletons forever, no error surfaced in the UI.

Notes
- The sidebar also lists sessions created on a *different* machine, so the chat
list appears to come from the cloud while local transcripts were never uploaded.
- Main log contains only [REACT_QUERY_CLIENT] QueryClient error: "Not found"
from assets-proxy — no other errors, nothing logged when a chat fails to open.
- CLI 2.1.263 in Terminal works normally, including --resume on the very same
session files the app cannot render.

Already tried, no effect
- Cleared app Cache / Code Cache / GPUCache
- Symlinked the CLI into /usr/local/bin (installed via Homebrew at `/opt/homebrew/bin/claude`)
- Removed stale ~/.claude/ide/*.lock
- Moved every transcript over 50 MB out of ~/.claude/projects/

Reproduce the failure in the desktop app's Code tab using a session under ~/.claude/projects/, then inspect the main log around the assets-proxy "Not found" error. Compare local-session loading with a cloud session and CLI --resume; done means the local transcript renders and the composer can send messages.

Written by the indexing model from the issue text.